update on this because I had an idea and it worked: getting class state corrupted will remove the collar, and since the ram transformations don't have any overlap with werewolf transformations, this can be used to get rid of the collar without getting rid of any werewolf transformations
not quite, since the collar doesn't show up in the 'status' tab in the menu, and that's what you use to get rid of transformations using crystals. as far as I can tell, the collar is only added by losing to the werewolf in the outskirts tile in A11, and the only way I've found to remove it is with class state corruptions (having your color get overridden by a monster's)