try these to start:

I am not an expert at looking xrays so can’t help you there. however, if that is his front view, i would say that his left pelvis is higher than his right.  if you lay him down and pull his legs straight, i bet his legs are of different lengths. give that a look. however, i would first test the assumption that it is fixable and not a structural problem.

for the knee, try:

For your friend with the hip, he has a CAM hip. Look for that, Kelly talks about tha in some of his videos about internal rotation (he is talking about mushrooms when talking abou it i think 😉 ) = hip impingment !!.

He really need to work with distraction!!!! always, try to get as much of mobility as you can and work on evrything around it like David was saying. Definatly work on glutes  and posterior capsule of the hip !!!!

Work on i but be gentle , listen to the body, cuz his cam is here and he can dameg his capsule/labrum when he overdoes!!!!

Greetings from belgium

I’m looking for videos in pro daily rx for this hip issue but it’s very hard to search.