https://ibb.co/album/0pc5w2
Lord Banehollow runs the Island and Circus when the Faire is not up. Lord Banehollow is a Nathrezim and the Nathrezim serve Sire Denathrius which means he is the one really calling the shots on Darkmoon Isle which is probably an Island somewhere in the Death Realm of Revendreth.
Of course the Warlock Players are going to kill Lord Banehollow in the Questline so his master Denathrius will probably hear the news and realize that someone from the Warlocks is going to blurt out the truth forcing him to drop all pretense and hopefully remove the still being constructed Exposition Pavilion and build his new Keep in it’s place so that he can personally make his ownership of the Island and Circus official.