Could you part/ if needed trim some of the feathers around her vent, so we can see the area a little better?
From what I'm seeing it appears she has had a cloacal prolapse. That is predominantly caused by internal pressure inside the vagina due to an egg, or buildup of fecal matter. Seeing a vet will likely prove the best prognosis, but if that is not an option, I would try picking up some Preparation H, or some DMSO gel, and apply a good coating around the area. That will help reduce some of the swelling going on, to the point you may be able to gently apply pressure and tease the tissue back in.
In addition, keep her in a warm, humidified room, and offer her sugar water or an electrolyte often. Administration of a calcium supplement such as tums, or calcium gluconate may prove beneficial if the problem is related to a calcium insufficiency.