So, we do all this preparation for the Policeman's Ball and then no mention of it again. It would be nice to be able to see the ball, even if it's just a bunch of NPCs standing around in a special room.
What, you expect them to actually have the ball after going to all those preparations? If it is not justified to do the preparations for their own sake, then why do them at all? In Marleybone, it is the journey that matters, not the destination. :D