The problem was that these guys didn't have any sleep. Lots of people think like they're against Sicilians When Death Is On The Line and that if they just slow poison their folks they'll become immune to poison. Well, just like giving your children small amounts of mercury every day doesn't turn them into a mercury-immune kid, not letting people sleep doesn't lead to sleep immune people. It just transforms people into idiots. So they transformed all their people into idiots. And then the idiots crashed the boat.
If you did the same to me, I assure you I would be even stupider and my performance even more lacking.