If Lorca isn’t from the MU, then at a minimum he intentionally took the ship there for some reason. He’s undoubtedly hiding something.Until now, I couldn't definitively pin down Lorca. I was mostly sure he was from the mirror universe. There was a moment in this episode that completely verified that all of the "where the hell are we?" stuff is an act. Burnham(was it Burnham? Maybe Saru?) suggests looking back through the navigational records to see what went wrong. He immediately cuts her off with his own theory and how to proceed, covering up his deed. This can only delay the inevitable discovery of his "override."