I know a guy with what sounds like a similar condition - in his case most of the colour receptive cells in his retinas are fucked, it’s a genetic thing that ment they didn’t form correctly in the first place. Not really anything you can do surgically, it’s not like cataracts or stigmatism where the retina is ok but the light isn’t reaching it correctly.

He wears highly tinted sunglasses cos it turns out that those colour cells are also really heavily involved in adjusting your iris to ensure you get the right amount of light, so his eyes adjust to changes in brightness much slower than normal which can be physically painful if he (eg) turns on the lights in a dark room