hmm i dont know which tests are necessary for the license in america but in germany you only need to do a simple test where you read letters from a board.
but if you have epillepsy you will lose your license untill you are free of sizures for 6 month. but how should a doctor test if you are still having visuals because of HPPD there is normally no scan which shows a result. so you are able to lie and the doctor cant prove.
but if you think that you arent able to drive safly its your decission. i dont want to kill childreen in an accident. but there are people who are mostly blind still drivin so i think HPPD is in the most cases not prevending you from driving safe.