What additional sensory information would you expect a person with impairment of organs of equilibrium to use to supplement their relative lack of some sensory information?

The equilibrium organ is supported by vision. That is why closing your eyes can reduce your ability to keep your body in balance. Even if you don't feel rotation on your body, your eyes can detect it visually.

So, a person with impairment of organs of equilibrium would compensate their lack of sensory information by their eyes.