Hello, just signed up after looking for this exact topic. We have been caring for the high school's cornsnake for the holidays and he also vomited/regurgitated 6 days after eating. (Yes, 6 days.) Definitely a regurg, not a poop with skin. The mouse was pretty intact. I did not examine it too closely as it was very smelly, but I did see at least one area of digested fur and skin where ribs were showing. He does tend to regurgitate now and then, usually only at the school where there is more stress with all the kids around, and one in particular who kept handling him after eating despite being told not to. As for the 6 day regurg, the tank may have been a bit too cool. Turns out my daughter did not have the UTH plugged in since he is next to the baseboard heater in her room and the temp tape showed 80 degrees. However, the science teacher has the tape up along the top of the tank so I told her it could have been too cool at the bottom where he was and she plugged it in a couple days after he ate, but it was probably too late by then.
He was very lethargic during those 6 days, but after he vomited, he was much more active and seems fine now. He also did a lot of burping, and perhaps farting during that time. My daughter is pretty sure she was hearing farts, anyway. Next week I guess we will try giving him a fuzzy instead of a grown mouse and see how he does. He is about 45" long and has been fed on adult mice for at least the past 1 1/2 years. Would it be better for him to switch to several fuzzies a week instead of an adult mouse per week as they seem like they would be easier to digest?
Oh, also what little poop he is passing from that mouse is a light green color. Is that a concern? It's usually quite brown. I can speak to the teacher about having him go to a vet if he keeps regurgitating, but the nearest reptile vet is 120 miles away, so I don't know if they will do that.