Okay. Can you make some sterile saline solution for cleaning it? Boil some water and let it cool. Add 2 tsp salt into one quart of the boiled water in a clean quart jar (ideally, a sterile jar). Add a pinch of baking soda. Put a sterile lid on and shake to dissolve. I like putting some of this...
What is this wound you are showing us, where is it on her body? Do you think the other chickens did this to her? When did this wound first appear and how are you treating it? I'm sorry this is happening.