What did you mean by Ground Zero photos? Just the name for his current habitat and the mite extermination zone? Lol
Are these photos more recent than the original post? I only ask cause he looks a bit more dehydrated and I feel like I'm seeing more red around his scales... If he's about to shed than that's probably why though.
If not... I would definitely be worried about septicemia and crossing my fingers the vet can see him soon.
Another possibility for the injury as well... I don't know why we all didn't think of it sooner... Maybe the mite concern made it slip my mind. It could be a gnarly rodent bite that had abscessed/healed over badly as well. Usually snakes develop more like a thick cyst material in an infection, but if it was too large of a rodent and some deeper wounds that can be why it looks a bit more burn like. So that could be why if the previous owner had been feeding live