I'm trying to get to the last lore vault, right next to where you start the game, but I can't find any path to get there after hours of searching.
Just to the left and above that vault is in the circular clearing in the nearby northwest. You need to punch together the wall on the right side so it makes a complete half-circle. Jump around the circle counter-clockwise and land on the platform in the middle, then hit the button. If the button's not lit, you need to activate the nearby power orb.
Jump back on the wall on your left and continue counter-clockwise and climb the now-elevated archway. Jump your way to the now-accessible area.
Here's a video:
Wow, I stood in front of that button in the circle a bunch of times and there was no interaction prompt so I thought I had already hit it. But it turns out, the prompt only appears when standing behind the button, not in front of it.