Weird thing is, he is not on the top 10 list, which means dude didn't wagered much enough to go to top 10 and still won or maybe he is one of the hidden ones but if he was hidden than we wouldn't see his big win, which means its unlikely that he became hidden later on, he probably didn't wagered much neither before nor after the big win, that is a huge profit in any calculation ever.
Usually, winners of the contests are those gamblers who wager on small odds with high probabilities. As the total wagring amount determine the winners, in this way they can play for a long time and increase their wagring volume. They try to play with low risk and lose as little as possible.