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)