Thanks guys, the tank had already been cleaned out about 20 minutes after they brought him in, I couldn't let him sit in that filth any longer. On my way to picking him up, I called the store vet and made an appointment for tomorrow morning. He's now sitting on top of my dresser with his heat pad and a ceramic heater on a rheostat to get his core temperature up.

He's right now settling down from the drive over and being really active, he actually looks quite healthy if you ignore the belly and old skin.

I probably shouldn't have listed the frozen mice issue first, it truly is a small issue. I have no problem getting to my own store to get mice, it will just be easier in the next couple of years, when I no longer work there, for me to get about 50 frozen rats and thaw them when I'm ready, and besides, I never did get to fee my corn snake live...

Thanks again for all the advice Richard and Rapture, I think I'll leave his shed be and let the vet take care of him. He's really calm and docile but he's been through a lot in the past few days, I'll at least let him rest until his appointment tomorrow morning.

I'll definitely let you guys know what the vet said later tomorrow, let's hope for Zeus' (his new name) quick recovery!