There are many whales who might be wagering big amounts but not all of them turned out to be lucky and in the above case he has wagered on many matches and combined odds gave him such a big win but he must be having knowledge for them as well.Being lucky was another big contribution to his win and without it he would have lost that amount also.
A parlay composed of price spread type of bets only show how calculated his bet is. Maybe he is lucky by I would say that he gives a thorough analysis on his bet in able to come up with that kind of parlay build.
If he is just betting randomly, He will choose match winner because it’s easy to pick bets using a 2 choices only compared to price spread that has a lot of option depending on how much knowledge he got to the team that he is betting with.
Winning at sports betting does not only depend entirely on luck but you are right where it also requires pretty good analysis too, because it is impossible for bettors to choose randomly and hope that there is a goddess of luck who will help the bet become a win especially for parlays because 1 match is enough for destroyed all the positive results in the chosen match, that's what I experienced some time ago quite sure that this would win and it didn't after one of the bets lost because one of the matches came out surprising, good analysis and luck will allow us to win parlay bets.