If you watch the finale trailer video and pause it at the scene where Zayday removes the mask of the RD you will notice writing on the inside of the mask. It seems to me it says "#2 Badcop"
i watched it and thought it said "backup", as in a backup mask probably for the costumes department or something-why would they give us a clue when that's the scene the killer is revealed anyway?
i was looking there to see a reflection! but i couldnt see one > _< i didnt notice any writing but i'm going to look again now..
What do you think?