I need help with custom viewmodel (FE GUN KIT) Thien's version, BUG

Okay, so the fe gun kit thiens he made it so you can use your avatars arms as the viewmodel, I love that features I just wish I could fix this bug.

He uses R6, a lot of bundles don’t support R6, for example if you look at the blocky version of R6 it has no character mesh, therefore the viewmodel doesn’t change, same thing for other bundles.

How could I make it so it supports every bundle? The bug is that if you use a blocky avatar and go in first person, it won’t be the blocky arms as your viewmodel how do I fix this so it shows your avatars arms?