Right now I'm stuck in an area of Gnah Lake cavern where there are four switches corresponding to a direction. A sign says "Which way did you come in?". However, despite having entered the cavern by going right and having entered this area by going up, only the switch corresponding to "Left" is doing anything and the grid won't open.
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I assume that this is the cavern where you get the item allowing you to go through shallow waters, but I might need some help solving this puzzle.