Hi, very interesting thread here!
I am curious, are all your birds free ranging? Because, with a prosthetic, she may do well in the run with the others if they don't bully her badly.
I'm also very curious what a chicken prosthetic leg would look like! So keep us updated
She's very beautiful. I like the green legs on these EEs.
As far as indoor advice, I've only kept them temporarily in chicken hospital, usually under my art desk or in the laundry room. But they wouldn't move around much. Perhaps you could use a dog crate or a large cat carrier- or one of those cat litter boxes with tops. They should all have a small lip around the door, hopefully not too high for her to have trouble crossing, but high enough to keep bedding inside.
Another option would be sand bedding... probably not the best choice for comfort, bacteria, or temperature, but it wouldn't fly everywhere, and it would be easy to scoop clean.
I've never dealt with chicken diapers, but i'm sure you're also looking into that.
Best of luck with your beautiful girl! If the dogs are protective of her, I'm sure she will be fine. She will need a big brother or two to watch over her through life.