Poor things, you are doing them a favor they will grow into loving. When they are that dirty though, will they get chilled by getting soaked in a rain? If they haven't been grooming, do the feathers with poo sludge have no water-repellent oil on them?I’m not sure if they would agree with you, Just now, but thank you. It is supposed to rain tomorrow... I am hoping that that will help get them clean. They are confused by the grass they are on, and going to be penned in a meat tractor until they are clean.
The ones I'm trying to rehome had a great start with the caretaker I think, and when he left, it's the returned homeowner now who "hates chickens" and is doing virtually nothing consistent for them. He has a poor cat who is also neglected, needs vet care and more - he was trying to eat the chicken feed and mealworms I had with me.