Oh I can list steps I did to find it.
1. get yellow medkit as a human
2. get transfurred by the goo wolf DIRECTLY by a wolf. No puddles as that will just make the medkit do its intended function. Also AVOID the intended soft lock. it ruins all chances of you seeing the bug. walk away from the wolf to disable its chase.
3. stay as the wolf for a little while. you will see you auto rub DESPITE Having the yellow medkit. Oh and yellow medkit does not end softlock as you intended. so look into that as well.
Hope this helps. love the game.