Jason,
Sounds like he is in a better place already. I get so sick of people who claim to know how to keep snakes, when they really don't know JACK. But then again, drys are not quite the same as any other snake. They require attention to detail.
My word is far from gospel though! And I would say that they are not totally arboreal, but equally at home in the trees. I base my opinions on what I observe. And I have not observed BTs in the wild. But one other indicator of their arboreal preferences is the fact that all my indigos, when picked up, always try to go in a downward direction, and they always look downward. With cribos it is the exact opposite. They always try to look, and go up, and will readily climb on branches or anything else. And they are quite good at it. Also, another hint is body structure. Indigos tend to be not quite as long as cribos, and much thicker. Where as Cribos, when compared to indigos, are built for climbing, long and slender.
I feed all my drys anything they will eat,...{{within reason}}. And everything must be pre-killed, and frozen for at least a couple weeks to kill any possible parasites. Todays menu began with a few minnows, which I trapped in a local creek. Then they got some chicken gizzards, followed by a couple mice. If your cribo refuses rats, he's not hungry enough. Let him get hungry. If he still refuses, rinse all the rat smell off, and rub mice on it. And/or give him a mouse, and then sneak in a rat. You may need to do these tricks a few times before he looses his repulsion for rats. Here is the short list of my dry menu; chicken wing segments, hearts, and gizzards, quail, fish such as minnows, trout, catfish, salmon etc., rats, mice, baby bunnies so far. But drys will eat just about anything they can swallow, including other snakes frogs, lizards, bats, and who knows what all. My advice is to try new things, and see what turns him on. After a while, he won't care what you toss in there. He'll nail anything that you offer! Including you, if you're not careful!! Right now, he just doesn't know anything but mice, because no one has ever given him anything else. He'll learn if you work with him. I promise. Use his hunger, and excitement as a tool to get him to try new things.
T.