Obviously they are done with infiltration already. Now that you mentioned it, I suppose one possibility could be that a single adventurer with their henchmen has managed to take control of Minami, more or less (an evil version of Shiroe) and could be planning to add Akiba to their regime by making Round Table lose face and offering the Akiba residents a "better" choice.
We have two eps left, so I'm not exactly expecting a too marvelous plot from this arc. Unless they end the show in the middle of an arc. That would be novel.