Have followed up with any of the people you have seen?
Did they give you any treatment plan?
Have you continued to have it worked on?
Yes, you play basketball 4 times a week, but continuing to work on it gets it back into where it needs to be.
As you continue working with it the corrections will hold longer. You need to retrain the position/muscles on the correct positional changes.
Yes the opposite side may make compensations based on what is happening with the other side.
Do you have limitations in your leg rom?
Have you addressed your diaphragm at all?
This can impact those areas.
If your hamstrings are tight spend time on them.
Here are some to start with:
High Hamstring Gnar, Trigger Points, and Up Stream/Down Stream
Episode 354: Make Your Own Super Floss/High Hamstring & Hip Gnar Gnar
Episode 272: TJ Murphy Edition and Hamstring Stiffness
Episode 137: Best Hip Extensor (High Hammy) Mob and Better Jerk Shoulders
Episode 104: Hammer Your High Hammy
Episode 82: Protect your scrotch or: Medial hamstring fun
Episode 58: Weird Hamstring Problems and Simple Neurodynmaics