Petsmart will do the return, regardless of if it passes or not in the 14 days.
Sadly yes, they best Petsmart can do and what they are required to do is take it to the vet. I've had a few amazing vets at my store that will do what they can, but sadly this is pretty extreme so euthanasia is the most probably outcome. I think the most frustrating aspect I've had is vets telling us they can't see a critical pet immediately =_=;