Script creating part, but not creating weld? What am I doing wrong?

I have a LocalScript inside the player(s), which records if a player presses, and releases a certain key, which in this case, is Z. Pressing the key fires the GomuPistolEvent and KeyHeld = true, releasing the key fires the GomuPistolEvent and KeyHeld = false. I recently had a problem, which was quickly fixed, but now my issue lies from lines 69 to 94. I run tests to check if the part "ArmStretch" is being created, which in fact it is, and since it is unanchored it falls to the ground through the map. The "Weld" isn't being created for some reason, and I'm not getting any error messages. I have also tried rewriting the code to create weld to "Weld = Instance.new('ManualWeld')" but that doesn't seem to work either. What am I doing wrong?

Big Thanks!

Code:

--//Services
local ReplicatedStorage = game:GetService('ReplicatedStorage')
local ServerStorage = game:GetService('ServerStorage')
local ServerScriptService = game:GetService('ServerScriptService')
local Players = game:GetService('Players')
local GomuRemotes = ReplicatedStorage.Remotes.DevilFruits:WaitForChild('GomuGomu')

--//Variables
local GomuPistolEvent = GomuRemotes.GomuPistol:WaitForChild('GomuPistolEvent')
local DamageModule = require(ServerStorage.Server.DamageService)

--//Animations
local GomuPistolAnim = Instance.new('Animation')
GomuPistolAnim.AnimationId = 'rbxassetid://2188557970'
GomuPistolAnimTrack = nil

--//Coding
GomuPistolEvent.OnServerEvent:Connect(function(PlayerWhoSent, KeyHeld, Mouse, MousePosition)
    local Character = game.Workspace:WaitForChild(PlayerWhoSent.Name)
    local Humanoid = Character:FindFirstChildOfClass('Humanoid')
    local RightArm = Character:WaitForChild('RightLowerArm')
    local RightHand = Character:WaitForChild('RightHand')
    local LeftArm = Character:WaitForChild('LeftLowerArm')
    local LeftHand = Character:WaitForChild('LeftHand')
    local Damaging = false
    local Attacking = false
    local Damage = nil
    local Cooldown = nil
    local Range = nil
    local BodyGyro = Instance.new('BodyGyro')
    local BodyPosition = Instance.new('BodyPosition')
    local ArmStretch = nil
    local Weld = nil

    if KeyHeld then
        BodyGyro.Parent = Character.LowerTorso
        BodyGyro.Name = 'SkillGyro'
        BodyGyro.D = 100
        BodyGyro.MaxTorque = Vector3.new(math.huge, math.huge, math.huge)
        BodyPosition.Parent = Character.LowerTorso
        BodyPosition.Name = 'SkillPosition'
        BodyPosition.Position = Character.HumanoidRootPart.Position
        BodyPosition.MaxForce = Vector3.new(math.huge, math.huge, math.huge)
        GomuPistolAnimTrack = Humanoid:LoadAnimation(GomuPistolAnim)
        GomuPistolAnimTrack:Play()
        GomuPistolAnimTrack.KeyframeReached:Connect(function(Keyframe)
            if KeyHeld and Keyframe == 'Charge' then
                GomuPistolAnimTrack:AdjustSpeed(0)
            end
        end)
        print('pistolcharge')
        Attacking = true
        while KeyHeld do
            MousePosition = Mouse.Hit.p
            BodyGyro.CFrame = CFrame.new(Character.LowerTorso.Position, MousePosition)
            wait()
            if not KeyHeld then
                break
            end
        end
    else
        GomuPistolAnimTrack:AdjustSpeed(1)
        print('pistol')
        BodyGyro.CFrame = CFrame.new(Character.LowerTorso.Position, MousePosition)
        GomuPistolAnimTrack.KeyframeReached:Connect(function(Keyframe)
            if Keyframe == 'Pistol' then
                GomuPistolAnimTrack:AdjustSpeed(0)
                Damaging = true
                Damage = 25
                ArmStretch = Instance.new('Part')
                ArmStretch.Parent = Character
                ArmStretch.Name = 'ArmStretchRight'
                ArmStretch.Color = RightArm.Color
                ArmStretch.Size = RightArm.Size
                ArmStretch.Anchored = false
                ArmStretch.TopSurface = 0
                ArmStretch.BottomSurface = 0
                ArmStretch.CanCollide = false
                RightArm.Transparency = 1
                RightHand.Transparency = 1
                Weld = Instance.new('Weld')
                Weld.Parent = ArmStretch
                Weld.Part0 = ArmStretch
                Weld.Part1 = RightArm
                Weld.C0 = CFrame.new(0, 0, 0) * CFrame.new(0, 0, 0)
                while Keyframe == 'Pistol' do
                    ArmStretch.Size = ArmStretch.Size+Vector3.new(0, 0.1, 0)
                    if ArmStretch.Size.Y == Range then
                        ArmStretch.Size = ArmStretch.Size-Vector3.new(0, 0.1, 0)
                        if ArmStretch.Size.Y == 1 then
                            break
                        end
                    end
                    wait()
                end
                GomuPistolAnimTrack:AdjustSpeed(1)
                Character.LowerTorso:WaitForChild('SkillGyro'):Destroy()
                Character.LowerTorso:WaitForChild('SkillPosition'):Destroy()
                Character:WaitForChild('ArmStretchRight'):Destroy()
                if RightArm.Transparency == 1 then RightArm.Transparency = 0 end
                if RightHand.Transparency == 1 then RightHand.Transparency = 0 end
                Attacking = false
            end
        end)
    end

    RightArm.Touched:Connect(function(hitPart)
        if Attacking and hitPart.Parent:FindFirstChild('Humanoid') and Damaging then
            Damaging = false
            local HumanoidToDamage = hitPart.Parent:FindFirstChild('Humanoid')
            DamageModule.Combat(HumanoidToDamage, Damage)
        end
    end)
    LeftArm.Touched:Connect(function(hitPart)
        if Attacking and hitPart.Parent:FindFirstChild('Humanoid') and Damaging then
            Damaging = false
            local HumanoidToDamage = hitPart.Parent:FindFirstChild('Humanoid')
            DamageModule.Combat(HumanoidToDamage, Damage)
        end
    end)
end)