Right at that last right turn that leads to the telepad at the end of the cave, there's a dead end if you turn left. The camera is angled so that you can't see him; the stupid wall is in the way. Just press X until a text box comes up. There's at least one person at every dead end of the cave.

If my curiosity didn't get the best of me, I probably wouldn't have found this guy. I just decided the developers might have put someone in a spot where you can't see them. =P