Just keep her wound moist and clean. We had a similar thing happen to one of our piglets on our farm. We changed the bandage often, and put triple antibiotic ointment and bag balm on it. Slowly, it got better, it ended up being one of our nicer showpigs. Keep in mind that you want to change the bandage often and keep it clean. You also might want to temporarily separate it from your other chicken as the might peck at the wound. Good luck!!
Some years ago I had a huge Embden goose that was attacked by one of the neighbors dogs. That dog chewed the butt raw on that poor goose. I went to the vet and he gave me some stuff that you spray on. I can't remember what it was called, but it healed his butt nicely. You might want to call your vet to see if they have something for it. I also want to mention a product that I use on open wounds on my horses. It is called Underwood Horse Medicine. You mix it with baking powder or apply the baking powder after you spray. I never tried this on a chicken, so here is the number 405-665-2682 and you can ask them directly. I got this stuff at big R and even some lumber yards carry it. If you don't want to bother with that, go to your vet and pick up some Verericyn VF. It is wound and skin care and safe for chickens. This stuff is awesome but expensive..
As for the heat, Your chicken is probably experiencing inflamation from the wound and that is why she feels warm. Just watch for infection. Smell the wound after each dressing and note any changes. If it starts to smell foul. Get her meds immediately. Vertericyn VF my be the way to for this bird. Please keep us posted on her!