I dont think he himself in particular has said so, but I believe someone in this thread mentioned that one symptom of moebius syndrome is that you cannot move your eyes individually from your head, like depending on how severe it is, the muscles responsible for eye movement are affected along with the ones responsible for moving your mouth--so if it's that, he would be unable to pass the vision test to get a license.
It's suspected that that is the case, though, and it explains why his handwriting is so shitty and inconsistent. For example, his "let me take you on a date, Taylor Swift" posterboard project where he wrote shit like "LET ME Take you on a date taylor swift IM A REally cool guy" in crayola markers and had one of his paralegal coworkers photograph him during office time.