Get some Vetericyn wound spray. The gel works great as it sticks to the wound. You will need to apply it several times per day and keep the chicken isolated (somewhere with no flies too) while it heals. By the 2nd day, it will be scabbed over. This stuff is amazing.
Also, you can give her 1/4 aspirin crushed in 1 cup of water for pain. She will be in shock for a while. You will probably have to dribble it on her beak to get her to drink it.
Chickens are amazing healers, but they also do not show pain - so it's very difficult to decide when to put them down.
Also, I edited your post above and put your pictures in a Spoiler, so those that do not want to see the graphic pictures do not have to look.