From what I understand, if he has 2 of the same roll he enters reach mode and it will create a hype scenario and depending on the color of the ball, the door and the type of scenario the hype for the 3rd roll goes up. So basically a bigger chance for a jackpot and gaining a bonus (we dont know what kind of bonus yet)
In the chapter, the sequence went like this :
He hit two of the same character (the girl) and entered reach mode giving him the highest type scenario, a hype level over 80%. In this case, the girl didnt go home, he shouldnt have gotten the jackpot, it was a losing scenario. However, during the reach mode there is a chance that a "Chance up" will appear thus increasing your chance for a "Jackpot".
Which is what happened here, thank to the "Chance up", Hakari triggered a "special scenatio" and still obtained the jackpot.
TLDR : Hakari rolls a dice, if he gets the same number 3 times in a row, he gains a bonus