You can try adding fake eggs into the nesting box, that has worked for some of my pullets. I only have 2/6 that will actually use my nesting boxes the others lay under the raised boxes.
For future reference for others I thought I’d update this thread. Healing has been a long process we’re four weeks in now. Here’s what I did for treatment. I used vetericyn to clean the wound 3x a day the first week. After patting it dry I slathered it in medical honey link here...