Oh, right aha. I watched the scene again and Mob said he wasn't the one who shook the building so maybe that's what I thought? Well, either way... I still can't decide whether I think Mob knows about Reigen or not. I mean, Mob buys a lot of stupid stuff but sometimes it seems like he's figured it out. I'm not sure it's more than unconscious, though. It'd make sense to stick with Reigen either way.