Good idea moving him and see how it goes.
You may find that the other 2 cockerels as they get a bit older will cause some drama within the mix too. While you do have quite a bit of space, some just will not get along no matter what, so just monitor things. I move cockerels/roosters...
Good suggestions for wound care, I don't have anything to add for that. Barring infection, she should heal up o.k.
Question - she was attacked by an adult rooster. How old is this rooster?
How many adult (age?) hens do you have and how much space (sq ft) of coop/run do you have?
You have...