What causes dizziness and rhythmic body swaying?

[Cathy0319]

In 2014 I got very sick with asthma and GERD. I had a continual asthma flare for 6 weeks, being hospitalized and on steroids. When the asthma flare stopped, I was dizzy and imbalanced. I saw an ENT who had an MRI and VOG done. MRI was clear and he diagnosed peripheral vestibulopathy from VOG. Optometrist says convergence insufficiency and I started to wear progressive glasses. Had vestibular PT and symptoms improved. Able to square dance 4 nights a week for a year, until January 2016. Fell 2x in 24 hours, got 2 concussions  (per neurologist). Now dizzy every day. Rhythmic trunk oscillations sitting and standing, esp with eyes closed. Vertical diploplia. Poor balance eyes closed on firm surface and on foam. Normal MRI, normal temporal bone CT. Stumped vertigo specialist ENT, PT, and Neurologist. To see neuro ophthalmologist in May. Really tired of being dizzy and off balance. Any ideas?