I think that the popping sound on flexion suggessts that your ITB and Rectus femoris muscles are still very tight. Try doing your lateral releases all the way down the side of your upper leg to the patella and then push your patella in towards the middle. This will only work if you have your leg relaxed out straight whilst sitting.
For the rectus femoris stretching lie prone and bend right knee up as far as you can and use your left leg to gently push the right knee further back into flexion. This may well give you a popping, grinding or pain so if it does try twisting your right foot in or out until you find the most comfortable postion. If you can't do this comfortably then you should be very gentle and perhaps use ice or your cream immediately after.
I wouldnt worry too much about the actual technical diagnosis because physios create the treatment plan based on the signs and symptoms that we find. The only benefit of more investigations would be to to better advise how long the symptoms may take to improve.
It seems as though its already taking a long time so your exercises may not be quite right and need review again by your physio.
I would bias your strengthening for the quads in standing with the 30 deg limit and doing small slow/step ups and downs to improve control rather than just strength. in my experience straight leg raises in sitting or lying are a waste of time.
Good luck and let everyone know how you progress.