Make sure it stays moist. Triple Antibiotic Ointment can be used to keep the tissue moist.
Cortisone 10, with aloe helps with both inflammation, & moisturizing, if you can get some. This may help relieve the swelling of the area.
Looks like there's a peck wound on the prolapse.
Recently I was treating a prolapsed silkie hen(Caused by severe constipation, was originally told to treat it as if there was a blockage in the reproductive tract, this didn't help at all, & only prolonged the issue) I treated her constipation...