Illness/Sickness: Severely swollem cloaca, back legs held up

My GA male Aureus has presented with a severely swollen cloaca. He is definitely a large adult male, so this is not simply that presenting at maturity. The cloaca is "open", if that makes sense, and tissue appears to be sticking out some. It is around twice the normal size, and there is no fecal material showing to explain the enlargement. Otherwise, he is eating fine. He is in with several other males, so no way to tell if he is pooping or not (but everyone MUST BE, with the amount of waste these bachelors accumulate....). I am considering taking him in to the vet, in case of infection, but thought I would ask here first. This was not there yesterday, and I visually examine them all several times a day (obsessed...). Any advice would be welcome, can't post pics right now, but PM me a number and I can text them. Thank you!!!

Sounds like it could be a prolapsed cloaca. Definitely needs to be seen by a vet.

I have made him an appointment for this afternoon. How do they treat a prolapse?

This is what it looks like (I should say this is not my axie, this is a Googled image- mine are on a ceramic bottom with no rocks). This image is linked to constipation:
Photos of Sick Axolotls