If the story is actually true, then that's a fantastic result for the player. Still, I think this is purely about advertising he wants to make for the sportsbet site.
Why would someone post how much money they won on a gambling site? If I had won that much, I would prefer to keep it to myself. I certainly wouldn't want other people to find out that I would have won that much money. You can only risk it that way. Well, maybe people think differently. 1.4 million is a lot of money, by the way. Will gambling sites actually pay that to players?