I'm trying to get the Yureyu Key and I've read that I need to get inside the cave Saphira comes out of. I've even seen video guides on how to find the key. BUT: in the videos, as soon as they get inside this cave there's a rock that can be rock smashed on some stairs. When I get there from my game, though, the rock that's in that exact same spot is NOT a rock smash rock; it's just a regular, unbreakable rock. That makes it impossible for me to move forward; is it a glitch in my game or do I have to do something first?