Need Players To Be Able To Kill Humanoids But Not Each Other?

Ok. So here goes. This script is located in a gun. As of right now players CAN Kill Zombie Humanoids But can also kill each other. I've tried uncommenting the lines for anti team kill within the script located on line 8, 116, and 118 but everytime I do I get an infinite yield possible warning. I have tried to modify this script but have had no luck.

So all in all I need this to be able to kill my zombie Humanoids but not kill other players. Also I do have a team created just for the players called Humans, dont know if that helps but I thought I should let you guys know just in case.

Also the code is longer than this but I couldnt paste it all. However I posted the beginning up ti the function Fire as this is the important part

local Tool = script.Parent
local Handle = Tool:WaitForChild("Handle")
local Player = game.Players.LocalPlayer
local Mouse = Player:GetMouse()
local Camera = Workspace.CurrentCamera
local Character = workspace:WaitForChild(Player.Name)
local Humanoid = Character:WaitForChild("Humanoid")
--local TEAM = Character:WaitForChild("Team")
local VisualizeBullet = game.ReplicatedStorage:WaitForChild("VisualizeBullet")
local Module = require(Tool:WaitForChild("Setting"))
local GunScript_Server = Tool:WaitForChild("GunScript_Server")
local ChangeAmmoAndClip = GunScript_Server:WaitForChild("ChangeAmmoAndClip")
local InflictTarget = GunScript_Server:WaitForChild("InflictTarget")
local AmmoValue = GunScript_Server:WaitForChild("Ammo")
local ClipsValue = GunScript_Server:WaitForChild("Clips")
local GUI = script:WaitForChild("GunGUI")
local IdleAnim
local FireAnim
local ReloadAnim
local ShotgunClipinAnim
local Grip2
local Handle2
local HandleToFire = Handle

if Module.DualEnabled then
    Handle2 = Tool:WaitForChild("Handle2",2)
    if Handle2 == nil and Module.DualEnabled then error("\"Dual\" setting is enabled but \"Handle2\" is missing!") end
end

local Equipped = false
local Enabled = true
local Down = false
local Reloading = false
local AimDown = false
local Ammo = AmmoValue.Value
local Clips = ClipsValue.Value
local MaxClip = Module.MaxClip
local PiercedHumanoid = {}

if Module.IdleAnimationID ~= nil or Module.DualEnabled then
    IdleAnim = Tool:WaitForChild("IdleAnim")
    IdleAnim = Humanoid:LoadAnimation(IdleAnim)
end
if Module.FireAnimationID ~= nil then
    FireAnim = Tool:WaitForChild("FireAnim")
    FireAnim = Humanoid:LoadAnimation(FireAnim)
end
if Module.ReloadAnimationID ~= nil then
    ReloadAnim = Tool:WaitForChild("ReloadAnim")
    ReloadAnim = Humanoid:LoadAnimation(ReloadAnim)
end
if Module.ShotgunClipinAnimationID ~= nil then
    ShotgunClipinAnim = Tool:WaitForChild("ShotgunClipinAnim")
    ShotgunClipinAnim = Humanoid:LoadAnimation(ShotgunClipinAnim)
end

function wait(TimeToWait)
    if TimeToWait ~= nil then
        local TotalTime = 0
        TotalTime = TotalTime + game:GetService("RunService").Heartbeat:wait()
        while TotalTime < TimeToWait do
            TotalTime = TotalTime + game:GetService("RunService").Heartbeat:wait()
        end
    else
        game:GetService("RunService").Heartbeat:wait()
    end
end

function RayCast(Start,Direction,Range,Ignore)
    local Hit,EndPos = game.Workspace:FindPartOnRay(Ray.new(Start,Direction*Range),Ignore)
    if Hit then
        if (Hit.Transparency > 0.75
            or Hit.Name == "Handle"
            or Hit.Name == "Effect"
            or Hit.Name == "Bullet"
            or Hit.Name == "Laser"
            or string.lower(Hit.Name) == "water"
            or Hit.Name == "Rail"
            or Hit.Name == "Arrow"
            or (Hit.Parent:FindFirstChild("Humanoid") and Hit.Parent.Humanoid.Health == 0)
            or (Hit.Parent:FindFirstChild("Humanoid") and Hit.Parent:FindFirstChild("TEAM") and TEAM and Hit.Parent.TEAM.Value == TEAM.Value))
            or (Hit.Parent:FindFirstChild("Humanoid") and PiercedHumanoid[Hit.Parent.Humanoid]) then
            Hit,EndPos = RayCast(EndPos+(Direction*.01),Direction,Range-((Start-EndPos).magnitude),Ignore)
        end
    end
    return Hit,EndPos
end

function ShakeCamera()
    if Module.CameraShakingEnabled then
        local Intensity = Module.Intensity/(AimDown and Module.MouseSensitive or 1)
        for i = 1, 10 do
            local cam_rot = Camera.CoordinateFrame - Camera.CoordinateFrame.p
            local cam_scroll = (Camera.CoordinateFrame.p - Camera.Focus.p).magnitude
            local ncf = CFrame.new(Camera.Focus.p)*cam_rot*CFrame.fromEulerAnglesXYZ((-Intensity+(math.random()*(Intensity*2)))/100, (-Intensity+(math.random()*(Intensity*2)))/100, 0)
            Camera.CoordinateFrame = ncf*CFrame.new(0, 0, cam_scroll)
            wait()
        end
    end
end

function Fire(ShootingHandle)
    local PierceAvailable = Module.Piercing
    PiercedHumanoid = {}
    if FireAnim then FireAnim:Play(nil,nil,Module.FireAnimationSpeed) end
    if not ShootingHandle.FireSound.Playing or not ShootingHandle.FireSound.Looped then ShootingHandle.FireSound:Play() end
    local Start = (Humanoid.Torso.CFrame * CFrame.new(0,1.5,0)).p--(Handle.CFrame * CFrame.new(Module.MuzzleOffset.X,Module.MuzzleOffset.Y,Module.MuzzleOffset.Z)).p
    local Spread = Module.Spread*(AimDown and 1-Module.SpreadRedution or 1)
    local Direction = (CFrame.new(Start,Mouse.Hit.p) * CFrame.Angles(math.rad(-Spread+(math.random()*(Spread*2))),math.rad(-Spread+(math.random()*(Spread*2))),0)).lookVector
    while PierceAvailable >= 0 do
        local Hit,EndPos = RayCast(Start,Direction,5000,Character)
        if not Module.ExplosiveEnabled then
            if Hit and Hit.Parent then
                local TargetHumanoid = Hit.Parent:FindFirstChild("Humanoid")
                local TargetTorso = Hit.Parent:FindFirstChild("Torso")
                --local TargetTEAM = Hit.Parent:FindFirstChild("TEAM")
                if TargetHumanoid and TargetHumanoid.Health > 0 and TargetTorso then
                    --if TargetTEAM and TargetTEAM.Value ~= TEAM.Value then
                        InflictTarget:FireServer(TargetHumanoid,
                                                TargetTorso,
                                                (Hit.Name == "Head" and Module.HeadshotEnabled) and Module.BaseDamage * Module.HeadshotDamageMultiplier or Module.BaseDamage,
                                                Direction,
                                                Module.Knockback,
                                                Module.Lifesteal,
                                                Module.FlamingBullet)
                        PiercedHumanoid[TargetHumanoid] = true
                    --end
                else
                    PierceAvailable = 0
                end
            end

Narrowed Down Code:

function Fire(ShootingHandle)
    local PierceAvailable = Module.Piercing
    PiercedHumanoid = {}
    if FireAnim then FireAnim:Play(nil,nil,Module.FireAnimationSpeed) end
    if not ShootingHandle.FireSound.Playing or not ShootingHandle.FireSound.Looped then ShootingHandle.FireSound:Play() end
    local Start = (Humanoid.Torso.CFrame * CFrame.new(0,1.5,0)).p--(Handle.CFrame * CFrame.new(Module.MuzzleOffset.X,Module.MuzzleOffset.Y,Module.MuzzleOffset.Z)).p
    local Spread = Module.Spread*(AimDown and 1-Module.SpreadRedution or 1)
    local Direction = (CFrame.new(Start,Mouse.Hit.p) * CFrame.Angles(math.rad(-Spread+(math.random()*(Spread*2))),math.rad(-Spread+(math.random()*(Spread*2))),0)).lookVector
    while PierceAvailable >= 0 do
        local Hit,EndPos = RayCast(Start,Direction,5000,Character)
        if not Module.ExplosiveEnabled then
            if Hit and Hit.Parent then
                local TargetHumanoid = Hit.Parent:FindFirstChild("Humanoid")
                local TargetTorso = Hit.Parent:FindFirstChild("Torso")
                --local TargetTEAM = Hit.Parent:FindFirstChild("TEAM")
                if TargetHumanoid and TargetHumanoid.Health > 0 and TargetTorso and game:GetService('Players'):GetPlayerFromCharacter(Humanoid.Parent) == nil then
                    --if TargetTEAM and TargetTEAM.Value ~= TEAM.Value then
                        InflictTarget:FireServer(TargetHumanoid,
                                                TargetTorso,
                                                (Hit.Name == "Head" and Module.HeadshotEnabled) and Module.BaseDamage * Module.HeadshotDamageMultiplier or Module.BaseDamage,
                                                Direction,
                                                Module.Knockback,
                                                Module.Lifesteal,
                                                Module.FlamingBullet)
                        PiercedHumanoid[TargetHumanoid] = true
                    --end
                else
                    PierceAvailable = 0
                end
            end