For some reason, if I reloaded and got up there at the right time, Mortimer would begin walking later into his speech. My fix for this was to try and block his path while the bouncer and head waiter beat on me so as to keep him from leaving the room. After a couple of stimpacks and talking, Mortimer finally got to the end of his speech as he made it to the front desk, where I was able to out him and finally complete the quest.