So,generally one makes a claim on their insurance or the other party’s insurance and pays their loan. Is there some reason you don’t do this?
and while I’m not certain, I don’t believe a court will reopen a bk to add this reaffirmed loan to discharged debts. They reopen bk’s to address forgotten creditors and a fee various other reasons but this particular debt was already addressed so I would suspect the court would not reopen the bk for the purposes you seek.

