Hmm, sounds like someone has had some lessons in probability. As far as I can tell from the past challenge, Mr. Nguyen just has to guess words from a known list, so this is a challenge that could be won by chance unlike something like telekinesis. It seems that after failing the first test test needing to get 19/20, he now only wants to get 18/20 and is applying to five places at the same time. Maybe I'm a little cynical, but it sounds suspiciously like he is just trying to increase his chance of getting lucky.