I had a mild TBI 2 years 2 months ago and one of my disabling symptoms is dizziness (weird vision, imbalance, jello legs at stores etc.,). Few symptoms you mentioned are interesting and I do have them. Dizzy at big stores (weak legs), dizzy at stop lights and turning head and walking/talking I get imbalance. It is not vertigo and one ENT doctor injected steroids (I think) in my ear, vestibular therapy, vision therapy, chiropractor, cranio sacral therapy etc., and nothing changed. I also have other terrible symptoms like fatigue, dull headaches, tinnitus, facial pain etc., and all of them are 24/7 and only during nights for some reason my symptoms goes down and I feel some what o.k.

Few things worked for me are Myofascial pain release and Xanax (low dosage). I don't take Xanax anymore since it stopped working at low dosage. I will be going to Vision Therapy again with a new therapist since my other specialist "thinks" it is from my vision.

I am not sure where your doctor came up with 2-1/2 years. No one can predict and you may recover in few months. But keep trying all the therapies out there including vestibular. You never know. I am still trying........................