Glad you are so close with your vet, that will certainly make you feel more confident in either making the decision to euthanize or working with your vet to attempt to safe the BP.

Here's some threads from a member here "goldenburm" aka Peter (from the UK). Peter's done some amazing work with this female pictured in these threads and though I cannot speak for him, I'm pretty confident that he'd probably not mind a PM from you to discuss things. I'm not saying your rescue is saveable at this point, only you and your vet can decide that but I also wanted you to see what can happen. The BP Peter saved was a mess, I don't think many of us believed she'd come back so well.

Whatever you end up deciding please remember this community is here to support you through it and we're glad you've joined us.

http://www.ball-pythons.net/forums/s...ad.php?t=28174

http://www.ball-pythons.net/forums/s...ad.php?t=28699

http://www.ball-pythons.net/forums/s...ad.php?t=29365

http://www.ball-pythons.net/forums/s...ad.php?t=31179

I think I got those threads in order so you can see her progression.