Any advice? (Is this infection or tissue necrosis?)

[Katakornchicks]

One of my chickens got attacked by a possum about 3 weeks ago. He ripped her stomach open and I really did not expect her to survive. We've been keeping a careful eye on it, bathing her to wash the wound, and keeping her sprayed with blue-kote. She has proven to be remarkably resilient so far. She's eating normally, pooping normally, and even laying eggs. I can tell her mobility has improved as well. However, one of the deeper wounds has a bad smell coming from it which terrifies me. I washed her again, and then sprayed it all with fresh blue-kote after I took these pictures. I just want to know if that grayish crumbly area looks like infection? It's in a really awkward spot, under her leg, and it's hard for me to see or get a picture of. I've attached a picture of a bald chicken with a circle on the area so it gives you an idea of where it is on her. I can't tell if it's just dead skin or what, but I don't like the way it smells or looks. Any advice? Anything else I can do for her? I can't afford a vet sadly or she would have been there a long time ago.
(Also, I'm assuming all the yellow skin is bruising right? I was more worried about the chunky looking area than the yellow stuff)

 

[nuthatched]

Do you have any antibiotics?

 

[Eggcessive]

I would use Betadine or Equate First Aid Disinfectant from Walmart which can be used to disinfect the wound, followed by using plain Neosporin ointment twice a day until the wound smells better and appears to be healing. If you can get an antibiotic such as amoxicillin that might be helpful. Is there any drainage or do you feel an abscess?