Maybe it's just me, but game 5 really just has two options: Either you run and take the money or you split equally. Reason being that, once you decide not to run, you put your whole winnings at risk if the others decide to group up against you, for no gain of your own. That's made even more likely by the fact that, in order to get the case, you'll probably needed to screw some people, so they'll be even more incentivized to return the favor. Unless you're very sure that all people agree to screw one person in particular, sharing does not make sense.