Flexor hallucis longus dysfunction

Hi fellow physios

I have a patient, a professional golfer, who has a nine month history of medial foot pain around the left TDH region . He reports "ultrasound revealed an inflammation of the tendon". he has not brought in the report. MRI revealed no fractures or anything of other significance. thus far he has been treated by other physios with transverse frictions over TDH, tib ant stretches and dry needling, with unremarkable success. i assessed him for the first time last night so its all pretty fresh. he also reports significant left hip pain

my findings:
. his right hemipelvis is lower than the left in standing and his left leg appears longer in long sitting. I am a novice at SIJ-busy reading a textbook and hoping to do the Lee course in melbourne in december.
. he has exquisite tenderness of the FHL muscle belly over the fibula.
. I performed a TOG gait scan, the only remarkable finding being that he spends too long on his heel and puts no pressure at all on his midfoot during the gait cycle. he neither pronates or supinates.

My treatment consisted of soft tissue work through the entire FHL and gastroc, am SIJ MET and taping along FHL to offload it.
i am suspecting a FHL dysfunction but after reading the literature it seems surgery is the best option. has anyone had success in treating a problem like this conservatively?