I had an ACL repair to my left knee a couple of years ago, and a couple of years after my bike wreck. The MRI was done shortly after the wreck, but the surgeon in New Orleans said I could walk with it (which I could), and we could postpone surgery. Then I moved here to the PNW, had trouble on non-flat ground, saw a sports medicine surgeon.... who looked at the MRI and wondered what took me so long to have surgery?
So Pax, how's your opposite hip? I found that walking around on a bum knee threw my gait off enough that now I have trouble with my right hip.
I would say, get the MRI, and surgery. Don't wait. And do ALLL the exercises your PT gives you.