Chest Stretch Into Infinity Bug -- Only on One Character

[Splintered_Lizard]

I'm using the same mod profile for 3 different characters. Two behave just fine and, like this one, the second one was started on the first one's savefile.

 

Today I loaded up a previous starting area save to begin a third character, and changed her race and name via "showracemenu". I've done this before with no issues. I do this because I have so many mod settings I don't want to spend 2-3 hours tweaking again. But now when I go into sneak mode or she does certain stands her chest physics get all wonky whether or not CBPC is enabled. Of course this only happens on her being naked or wearing her BHUNP body slide clothing. 

 

Again I changed nothing else. I did quit, run FNIS again and go back in but still the same problem. I wonder what could be causing this issue? I loaded up my previous character and she is working just fine.

 

I also tried changing her sex to male briefly and back to female but to no avail.

 

I also tried rebuilding the bodyslide files but that too seemed to not do anything, unless I did that wrong.

 

Any help would be greatly appreciated.

Edited 6 hours ago by Splintered_Lizard
Added possibly relevant info.