I am unsure what the next steps are as I haven’t dealt with an issue like this. I have tagged some more knowledgeable people that are very good at giving advice for injuries.
Take her away from the flock and put her in a dog kennel if you have one or a box. Clean with saline and after you do that, take more photos of it and post them. It looks like a possible prolapse that got pecked at. Or just a vent that got pecked at. @azygous @Wyorp Rock @Eggcessive