The stop time of the random number generator, Kenny, is set by the individual maker of the machine. Some it’s when the first coin is inserted, others the moment the player hits the button that spins the reels. I believe the largest such manufacturer, IGT, triggers theirs by the initiation of the reel spin. Assuming IGT does this, it is highly unlikely that a player would have stopped the RNG at exactly the nanosecond needed to display the mega-jackpot combination on the screen if he had inserted the maximum coin amount, versus playing short. In that blink of an eye before inserting coin three, then hitting the button, the RGN would have cycled through thousands more combinations, so the player who hit the jackpot with one or two coins played, would almost certainly not have hit it with the maximum coins inserted.