No. Not dumb at all. Shaking the trees is just a thing to do. That was one of the many toys I put in, that has nothing to do with actually finishing the game. I tried my best to have people explore as much as possible to try different things, and that backfired with there being no instructions. 😔
The fishing mechanic I thought was easy to figure out, until all of my play testers told me it's not intuitive. You throw your rod in the water, and wait for the explorer to say "Fish!" and you rapidly tap on the use button to pull the fish out. If the meter gets to the top, the fish gets away.
The plumbkin is hard to find and tends to get lost very easily, I spawn a new one every morning near by the ship. If you walk to far away from it there's a bug where it despawns. I couldn't fix it in the time limit. :(