Looks like staph. Gently clean and use betadine.
That’s good to here. Sometimes I have newbies from 1-3 weeks old that crust over and almost it not so, stops their bowel movement, or so it seems. Mom sometimes does not do her job cleaning so you have to remove it. I use warm water with a little dawn dish detergent and a rag and soak it for a while then take the rag and pull it loose and clean it up. Many times I’ve added a dab of Vaseline over and around the Bum. Not my favorite job but once removed I normally have no further problems. In your case you had another problem also, glad you got it straightened out.An update! Just had him at the vet. It was some sort of an absess, they drained it, lanced it and gave him antibiotics and a cleaning solution to keep area clean. Scabs all fell off very easily, they checked them under the microscope (bit of a bacterial infection). He looks great now!