I would just clean it with saline, and apply some plain neosporin ointment on the wound. Tomorrow, I would call around and see if a local vet might see her. It does look deep with some exposed tissue underneath. Vetericyn Wound Spray is very good to use on deep wounds. Keep flies away from her. I would let her be with the other chickens daily in a dog crate with food and water, so the others do not peck the wound. She sounds like she will make it as long as no internal organs were damaged.