Is this vent prolapse or something else?

[Ebz5003]

This is Kanapki. She has been on and off pulling feathers or pecking under her tail for months now. She doesn't have lice or mites. Often now I'll see her vent/ under tail area covered in blood and I think what's happening is she is pecking there and making it bleed, and my bully of a Sapphire Gem is coming along and pecking at the blood, making it worse. I have to keep her in the garage and cover it with veterycn and then blukote, but blukote doesn't work for more than a day. I dont think she's laid an egg in a long time. I have this video and a picture. The vent area is the size of a large marble and moving constantly. Is this vent prolapse snd what should I do?