According to the internet (wikipedia) the odds of hitting a 10-Spot in Keno is near 1 in 250,000. We don't know how many games it took doll909 to hit the ten spot, and we don't know how long it will be until the next person hits a 10-Spot.
When "doll909" hit the ten spot on Keno Tap, they received 40,000 times their bet. So if they were betting be minimum of 1, they only got forty thousand credits, and if they were betting the maximum of ten million credits, then they now have an additional 400,000,000,000 credits to play with. Since I don't see "doll909" on the leaderboards with over four hundred billion credits, It's safe to say they didn't win the max amount.
One final time: Congratulations DOLL909!