Run back to the door and equip the head as a weapon. Executions immediately detach a head, where as hacking at a corpse requires a few swings. On the right side down the hallway is a case on the wall. Move up the stairs until reaching the top. Make you way to the door where the guard tells you he will not let you in because you are not a familiar face. In Episode 15, if you do not kill anyone besides Leo and sneak your way to where mental Pickman and Michael are, instead of saying 'Here's some more of your victims', Leo Kasper will say 'What? Have you turned over a new leaf?'