Mika might not be able to follow him very well if he was specifically trying to lose her, but that isn't the case. She almost gets lost once or twice, but with the creature jumping up and down to show her where he was, it wasn't too hard to reorient herself. It helps that she's not exactly huge either, and thus doesn't have too much trouble slipping through the crowds. Anyway, she eventually arrives at the vault door. "Almost lost you a couple times there... Alright. Let's see what you've built up."