Yep, this one is a bit tricky to diagnose on a forum. You need to see someone with the skills in pelvic dysfunction. Often it is the opposite sides restriction that can cause the issue on the symptomatic side. Sometimes it is driven by the lumbar spine.

Suggest seeing someone with an interest in Muscle Energy Techniques (MET). This could be a physio, osteopath, chiropractor, Nordic therapist (where this all came from) etc. Many have the skills and many don't! So finding the right person is essential and I'd ask around for a personal recommendation.