I wont begin to try and diagnose anything, and as mentioned before it's probably time to suck it up and take time off to go to a specialist. Everyone is different and Dr. google only gets you so far.
From Dr. Googe: Sounds about right:
Iliotibial band syndrome causes pain on the outside of the knee. It might affect one or both of your knees. The pain is an aching, burning feeling that sometimes spreads up the thigh to the hip. You might notice this pain only when you exercise, especially while running.
That being said I can only speak to IT Band Syndrome for me and how I manage it. I have very mild scoliosis and as a result, my hips are uneven which leads to IT Band issues and piriformis pain on my right side. I never knew I had these issues until I started riding more regularly 10+ years ago. A massage therapist at one of the charity events identified these issues for me and it was confirmed by my doctor. Foam roller sessions and home PT stretches worked wonders for this on a semi regular basis, along with the now popular Theragun or copy cat types of devices. The biggest thing I learned was that I have to do some of this preventatively and not just after a ride. Nowadays sometimes I may have a very mild flare up its mostly because I didnt follow my own plan so its a good reminder.
Beyond that, footwear/footbeds and a cushioned mat under your feet would also be something to think about.
But after 3 months, time to go see a Dr. Just being straight up not being a jerk. Good luck hope it gets better.