I don't know anything about timing Jackpots, (not saying it's not plausible, anything is plausible with these sorts of devices) but I do know Ohio had similar machines (before casino gambling was legalized) that the State eventually came in and broke up. We had three of them here at the hotel, in fact.
Anyway, these machines were, "Games of Skill," or so labeled, and they presented an incredibly simple and unique vulturing opportunity. The machines had three different game denominations and all three denominations had a different game that was the, "Next Game." The part that allegedly (I mean, they were straight up illegal) made it a, "Game of Skill," was that you could hit the 'Next Game,' button and see if the Next Game was a winner or not.
That's basically how it worked, so effectively, when you made a bet, you weren't really betting on the Next Game, (known result, or could be) but rather the game after that. That's the skill, don't bet if the next game is a losing game. Anyway, most people didn't figure that out and would quit playing when they had insufficient credits, so then I would hop on that machine and check all the next games.
It wasn't worth a ton, even with how often I was here at the time, but I averaged a 100% risk-free $100/week on them before they took them out. The vendor didn't even care if we vultured them because we were paid a percentage of wins for housing the machines and were reimbursed losses. They would balance the cash drawer we kept in the safe for that and then we got some percentage of the overage.
I guess some of these types of machines are legal, or tolerated, if you're only winning merchandise credits...because I still (but rarely) see them at truck stops and gas stations, but I've not seen one with the, "Next Game," feature since.
I 'think' I'm following the flow? Can you run through a typical scenario where you'd do this then? So you'd look for people whom left their machines... If their "next game" was a winner, you'd play it? or ? I'm just genuinely curious how these 'skill games' work, but now also curious how you vultured them.