I can't disable player / NPC collisions if the avatar isn't blocky

Hello,
I tried to disable player and NPC collisions and used a script from the devforum and put it into the ServerscriptService.

This is the script:

local PhysicsService = game:GetService("PhysicsService")

local defaultGroup = PhysicsService:GetCollisionGroupName(0);
local playerGroup = "PlayerGroup";
local npcGroup = "NPCGroup";

PhysicsService:CreateCollisionGroup(playerGroup);
PhysicsService:CreateCollisionGroup(npcGroup);


function setNPCGroup(char)
	for i,v in pairs(char:GetDescendants()) do
		if (v:IsA("BasePart")) then
			PhysicsService:SetPartCollisionGroup(v, npcGroup);
		end
	end
end

function setPlayerGroup(char)
	for i,v in pairs(char:GetDescendants()) do
		if (v:IsA("BasePart")) then
			PhysicsService:SetPartCollisionGroup(v, playerGroup);
		end
	end
end


game.Players.PlayerAdded:Connect(function(player)
	player.CharacterAdded:Connect(function(char)
		setPlayerGroup(char);
	end)
end)

for _, v in pairs(workspace.NPCfolder:GetChildren()) do setNPCGroup(v) end

PhysicsService:CollisionGroupSetCollidable(playerGroup, npcGroup, false);
PhysicsService:CollisionGroupSetCollidable(playerGroup, playerGroup, false);
PhysicsService:CollisionGroupSetCollidable(npcGroup, npcGroup, false);
PhysicsService:CollisionGroupSetCollidable(playerGroup, defaultGroup, true);
PhysicsService:CollisionGroupSetCollidable(npcGroup, defaultGroup, true);

It works if you don’t have any body parts (most likely a torso) equipped on your avatar (If your avatar is blocky).
But if you have a torso from a bundle equipped, it doesn’t work. You still collide with NPCs or other players.

Here’s some information. I don’t know if this is important. (collision true / false)
blocky player + blocky player = false
blocky player + blocky npc = false
blocky player + not blocky player = true
blocky NPC + not blocky player = true
blocky player + not blocky npc = true
not blocky player + not blocky player = true