How should I keep the weld between a projectile part and an external model welded?

So I have a script where I am trying to create a projectile, set it's parent to the Torso of the player, and weld it to a bow model that is also attached to the player. The issue is that even though the weld is confirmed to be created, it isn't there where it is supposed to be. I assume it's been broken but I'm not sure why. Any help is greatly appreciated!

Code: https://hastebin.com/uwigozumok.lua