Though he had no inkling who or what Anthony J Crowley really was, Watson had the good sense not to keep him waiting long. He checked in on Holmes, to make sure the walls were relatively safe, before slipping out. It wasn't that he intended to dupe Holmes, but he did not care to answer the usual questions about his comings and goings. he was a grown man, as was Holmes. He could come and go as he chose.
He chose to go. His first experience with the port keys proved to be comical, and he had to ask someone for assistance to enter the London port key, to take him to Monte Carlo. Landing on his derriere on the other side, he needed a moment or three to collect himself, before attempting to stand.
Moments later, he was strutting in to the Eden Resort and Casino, bright eyes searching the area, in hopes of finding one Anthony J Crowley.