I'm confused; is it one or both feet? The foot in the photo looks terrible, is it only that one?
Penicillin injectable would be a good idea, as well as Silvadene ointment from the vet. i second checking with LA veterinarians, and also check at the vet path lab for names of veterinarians who do poultry testing, or who also treat chickens. Our state vet path lab has a list, maybe yours does too.
Dead tissue will fall off, and enough live tissue, and blood supply, needs to be in the foot, or it's totally dead and needs to go. Both feet, that's just wrong!
I also have asthma, and no birds can live in my house either. Get him out, how about a garage? If you get sick, he's not going to do well either. Your survival is more important, period!
Mary