FWIW, I wouldn't trust a pediatrician's vision screen at all! My DS, who is almost 8, has passed every single vision screen at the pediatrician's. They usually only test distance vision. My DS has a severe astigmatism that dramatically affects his reading ability but he is a very good squinter! He wears glasses when awake but can pass the pediatrician screen without them. He reads at an 8th grade level with his glasses on. Take them off and he *might* be able to guess his way through a kindergarten picture phonics book.
As for video games, if that is his love, go with it! My son learned to read playing Pokemon. It is very script heavy and you have to be able to read the directions and game play to get directions for what is next. I straight out refused to read it to him- forcing him to sound out and bumble through as best as possible. He taught himself to read playing Pokemon for sure! There are other text heavy games like My Sims Kingdom that also might work for what you need!
