Not everyone has the rotational variant.
I found that what fixed it was a combination of
..complete layoff for several months
...resuming climbing very gently and moving up to normal intensity and session duration over a 2 month period
...rehab protocol of 2 x 25 reps on 5kg ( moving up to 7), 6 x per week (double headed dumbell lowered straight down open handed, not single headed lowered rotationally at 90' as shown in vid)
..Tom Randall's stretch 2 mins daily. Key here was realising not just to bend a straight leg up backwards from the hip but to arch back up from the waist at same time. This is a lot harder than just bending lower body and a lot more intense.
This protocol 99% fixed in 2 months what had been resisting all other therapy for the previous 18.