I wish you all the best in your rehabilitation! Slow and steady is really the way to go.
Although, if he is really as malnourished as you say, I'm not sure I would wait for him to pass waste from the meal - we're finishing up Day 25 here with Buggsie and he's yet to pass anything more than urates and slight brown smear. We also started off super small with rat pinks, partly because we wanted to make sure we weren't over taxing his system right off the bat and partly because he didn't have the strength to handle anything bigger. I would love to see pictures of the snake, as well as progress updates.
I would also suggest caution as well as a good quarantine. He may appear to be healthy aside from the extended starvation, but there is no reason to risk your healthy animals. Plan for the worst, as they say. As much as I would also like to say resist getting attached until you're sure he'll make it, I couldn't keep myself from getting attached to Buggsie even while unsure if he would make it from one day to the next that first week. Although, if your little rescued buddy is actively moving around, he may be better off than you think, even though he's scrawny and underfed. Good husbandry can do wonders for these creatures and they are incredibly resilient, as I'm sure you'll find. I think it took 3 feedings and then suddenly it was like a switch flipped and our little guy went from being as listless as a sock to suddenly being active - moving and flicking his tongue. Hopefully you'll see as big a turn around!
Give your guy some time with good temps and humidity. I hope, for your sake and his, that the regurg was due to the prey being to large and not some other cause. To have lasted so long in such conditions, your new friend is certainly stubborn! Be stubborn with him, and see him through this to good health.![]()