Greetings
Tylexie,
Clean any open wounds with peroxide, betadine, or saline solution. Apply some Vetricyn spray, Neosporin ointment (without pain medication in it), Blu-Kote, or dab with colloidal silver.
Roosters and hens can chase and peck at her, causing damage to feathers, also grief and anxiety. So give her an edge by putting a hen saddle on her, provide enough space in the pen, free range them several times a week, add boredom busters like: plastic bottles (Parmesan cheese bottles with a flip top are great) with some scatch and or meal worms, fresh greens hanging around the pen, perches or platforms outside, a compost pen in the corner with some alfalfa hay, etc.
During long confinement, chickens need distractions that are a substitute for their natural foraging instincts. Otherwise they will pick on the most docile hens for entertainment or as an outlet for anxiety. This is a big problem for any animal in captivity.
I don't think you need to isolate any of the chickens, this sounds like a behavioral issue from stress.
Greens & fruit slices in large suet baskets.
A saddle/pancho for the smart hen.
The alfalfa pen, with a platform entry.
A lemon juice bottle with holes, for mealworms & scratch (too hard to fill). An empty Hentastic snack feeder on the left.
Well these are some of my distractions, you may or may not have some of your own.
These are my thoughts on your hen's issue, I hope they are helpful.
God Bless and peace to you.