I can believe it. I've hit 5 in a two day period before, including 2 in as many minutes.
This guy regularly streams on you tube from his phone with the lens just sticking out of the top pocket and plays at up to $500 a hand which is ridiculous because it's a handpay for every 3 of a kind! Usually pays $100 though.
They pay him with slot tickets so it's fast to reload.
Not sure if it's part of the win in this article but he hit the maximum buffalo's on Jerry Birl's favorite machine and won just over $1m jackpot, and that was just for a $25 bet (500 lines at 5c I think).

I guess he is just super rich and it all means nothing. He seems pretty honest about his play. He might win $100k on video poker and then admit he is still slightly down for the day etc.