I skipped a big part of it. A totally useless episode.

Isn't the slime geezer a logia user? Usopp should have seen the kind enough not to get ahead of himself and start celebrating. In any case he should logically forget the slime as much as possible and concentrate on Sugar. That's the mission, after all. But then again, like was said before, Usopp could have ended this whole fiasco even before it really began, being a sniper, so I guess it's fruitless to look for logic here.