It's a bit presumptuous to call someone a fraud. I've never done a single music exam, cannot read music fluently and generally have a poor knowledge of music theory but can learn complex pieces by use of the score & by ear. My abilities are as such: I can read music at a basic level as I started learning the theory as a kid, but as a lazy child, with ability but no will or push to learn I decided not to pursue the exam route (something I regret), however at 34 I've taken it back up. I memorise music easily and it's the only way I can play. I plug away & learn complex pieces, don't get me wrong, a lot of repetition is involved, but once it's in my head (and hands), there it stays.
I must apologise also, as I'm new on this forum & have just realised that I'm posting in a section above my station as it were!
But my point was, you don't have to have gone through the 'exam' motions to be able to play well.