Negan scout??

If the jacket model does have helper bones like the one you mentioned, lock it. If there isn't, leave them alone.

I was putting this on a scout model and everything went fine until I got into the hlp_forearms. Where are am I supposed lock them to?

I forgot to wrote in the description that this cosmetic only works with player model not HWM model. In the meantime, grab Maxofs2D's Enhanced Scout that will work with all shirt-based cosmetics and HWM friendly.
https://source.maxofs2d.net/?dir=models%2Ftf_scout_enhanced

how to fix sleeve issue pls

Cool!