It doesn't really count for your question, because he's like family, but my boyfriend cosigned ("endorsed") my Grad Plus (now Direct Plus) loans. To avoid bringing problems into his and my relationship, I asked two other old friends before asking him, but they both said no. I also asked a third old friend to cosign a smaller Grad Plus to tide me over one summer, $6600, but she was fortunately in a position to just loan me the money, so we did that instead.
Here's a loophole (word choice?) that you can discuss with your potential cosigners. When I graduated--actually a couple months before graduation--I consolidated all of my existing med school loans into a
Direct Consolidation Loan. (My loans from before med school were already consolidated.) The Direct Consolidation Loan paid off all my other loans, including my cosigned Grad Plus loans. My endorser received a paid in full letter and was no longer obligated. So your cosigner is likely (no guarantees) only obligated until you consolidate. I don't know, as an academic question, if you can consolidate while you are still in med school (for instance, consolidating M1 and M2 ASAP, and then consolidating M3 and M4 at graduation time, to minimize your endorser's exposure). I don't see why not.
The main consideration with consolidation is that your existing interest gets capitalized when you consolidate. This may not matter to you as much as getting your cosigner off the hook, however.
Another thing to keep in mind--Grad Plus loans are federal debts, so they can garnish a cosigner's Social Security(!!!) or tax returns, though I don't know how common this is in practice.
One thing you absolutely should not do is take out a private loan. I would wait out the clock for the bankruptcy to stop counting as adverse credit history (5 years as per
here) before taking out a private loan. I was 37 when I matriculated. You most probably have time. Private loans have (at best) very limited deferment and forbearance options, meaning that, essentially, the payments come due whether or not you have an income with which to pay.
As an aside, I did not consolidate in order to get my endorser off the hook, as we did not realize that would happen. I consolidated in order to get into
REPAYE (a payment plan) early and save some money, as per
this article. It worked according to plan.