Reading it again, the craziest thing is that from the very beginning, possibly from the moment he put down his card, Kaiji realized that if Kazuya doesn't fold at the doomed state (since Kaiji had more aces and the hidden 2s would also be established, if Kazuya lost more than 4 pieces, Kaiji would force a fold every single turn til Kazuya eventually loses off the forced 1 life per round), then Kaiji has already won. Because he had 3 reds, Kaiji always had 1 more life to bet. Kaiji always had the winning position, so Kazuya shouldn't have ever bet hard on a 50/50. This would mean Kazuya's only options from the very beginning were to either fold early or bet his own life. Basically Kaiji tried to stop Kazuya from betting his life from a long time ago.
It's honestly brilliant.