Hi, sorry to hear about your girl

If it is indeed whatever my boy had, she has a good prognosis. He survived, no one else ever came down with anything even close..He is quite the cocky little man today (he can walk completely under my RIR roo and not even bump his comb..lol..His face still has a wrinkled look to it where the skin was so stretched, but it doesnt phase him in the least.. He does have his own little band of 3 hens, but we dont ever incubate those egss just in case it was a genetic issue. I never did find out what caused it and he has not had any flare-ups or anything since. Hes as healthy as any other bird in my flock.
I did use the prednisone for a little over a week I think before I ran out..and I kept his food moist when he was at his worse so that I could be sure he got enough fluids and I kept Sav-A-Chik (both the probiotics and electrolytes) in with his moist food around the clock.. He does have an issue with crowing, but I dont know if it is related to this or not..
Best of luck..