Early in the evening, while the Kellers are still at the opera, Chorb arrives at the hotel and is greeted by the lackey, who leads him down the hall to the same room in which Chorb spent his wedding night.
When Chorb returns to the hotel with the prostitute, the lackey recognizes her as having spent nights there before. He gives her a wink, which we’re sure is appropriate given the circumstance.
The next we see of the lackey, he’s standing outside Chorb’s door with the Kellers, protesting that the man has a woman with him and now would probably not be the best time to go barging into his room.
When the prostitute flings open the door, the lackey motions for her to join him in the hallway.
Once the Kellers are inside with Chorb, the lackey and the prostitute lean against the door to listen, but they hear no conversation. The lackey puts his finger to his lips and says to the prostitute, "They don’t speak."