I'm with Doolittle on this one. He's really cool I know as a Kid and a Young man I had my fair share of wild collected Rat and King snakes but I almost always kept them for a few days to a week and then released back where I got them. Not saying you should put him back in your rodent rack, LOL.
But really he was born in the Wild and deserves to stay in the wild. I totally condone hanging onto him for a couple days, see if he will eat for you, then find a nice woodpile( Away from your rodent shed) and release him.
All in all though it's a really cool story!!!