After the first tie up along with hysterectomy I felt that ball feeling you are talking about. But unlike you I could see some tissue, smooth and slimy right at the opening of the vagina. I am pretty sure before prolapse all that was there was an opening at the vagina. What I felt was not pain; it felt like an object was there that shouldn't have been. The object itself didn't feel like it was part of my body,more like a foreign object, no nerve feeling in this tissue, but my vulva felt it. Also like you either stitches didn't dissolve or a staple was left after my initial surgery. After I recovered from hysterectomy my husband felt scraped during intercourse and one time was scratched and cut, even bled a bit. I went back to the initial surgeon who once again looked inside my vagina and cut a few things out. He cauterized the cuts, not any fun just giving me a local injection to numb the area high in vagina to cut these areas out. Yes once again I was sore for weeks. He told me the sensation I had of the tissue between my legs was normal and no issue. I couldn't imagine feeling this the rest of my life and of course it was most noticeable when I walked. I had it.
I saw another medical group who had a women's clinic and this ob/gyn recommended a women's pelvic repair surgeon who she said was a miracle worker for many of her patients and all he did was bladder repair. She wouldn't recommend any doctor in my town as the basic ob/gyn doctor wasn't specialized enough for this surgery.She told me what I was seeing and feeling was my bladder. The repair surgeon I saw said and that the tie up I had could not work because of thinning support tissue and yes I was seeing and feeling my bladder. He had great technology to show me what had happened and what he was going to do.
I was never told it was nerves feeling this way as clearly something was level with my vaginal opening. Evidently you have nothing view-able from the outside and you have had numerous doctors review your case. I assume you have seen a bladder specialist who is licensed to do the mesh surgery.

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