The problem isn't the snake. =\
You bought a cage and saw these issues and the issues are still going despite your attempts to fix it. Now instead of doing what should be done and getting a temporary but safe cagespace, you're letting your pet reinjure itself.
Have you checked the temps where his hides are? If he doesn't have proper belly heat that's part of why he'll be looking to snuggle into that mesh space.
As far as the cloaca issue.... It's not normal but I can't tell you what's happening. The belly scales also seem to be a bit pink? This could be something like a minor burn if he keeps trying to get up near the lamp and it's too warm. But hard to really say from photos.