I just had a realization the other day. In 19-2, Victor said one of GateKeeper's friends had told GateKeeper about Michael's job offer. Of course, Michael only announced to a few guardians, Pegs, and some field workers, including Amy. Bigsby was unconscious at the time, though someone may have told him. Seeing as this episode revealed Amy as being in league with Gatekeeper, I think she told him that Michael was going to be the new Sean. Not super important, but I think it is interesting