He is just showing the big payout that has been reached at rocketpot so far. Once there is a game reach the minimum payout for the jackpot (50x, 250x, or 1000x) then there will be a jackpot round. One lucky player who play during the game will be chosen to spin the wheel. In above linked round where 4k payout reached, it triggered the mega jackpot but unfortunately the jackpot was not hit by the lucky chosen player. Players does not need to get closer to the multiplier, as long as they are playing during the game then they have the chance to spin the wheel.
thank you for the explanation!

All the above is correct - I'd also like to add that if someone wins the jackpot, 10% of th value is split amongst ALL the other players who participated in the round, regardless whether they cashed out or were the ones to spin the wheel.
A week passed since you came to this forum and I can see there are more new names who play and hunt for the jackpot but I have never seen any single players who play normally. Normal means gambling for non jackpot purpose like what I usually see on other crash game sites. I dont think it is good for long term purpose unless you keep on filling the jackpot with good amount. I think you need to have other promotions such as wagering contest or other contest. To be honest, the jackpot amount you had at the beginning was so big enough to make a regular wagering competition and it may give you more players (not only jackpot hunters).