If you get tired of your crew members, aim (push or pull) the catapult until you see your ship through the spyglass. Then, push the rock and it will sink the ship. When you have the root beer and go back to the cave, Herman will approach and tells you that he actually has a ship, and is willing to loan it if you bring him back to Melee Island. When you complete Part 4, instead of seeing Herman searching for you, you will find your crew members in the Cannibals' guest hut.
To instantly win press Ctrl + W.