I'm honestly not sure how to think about these two random events. Perhaps just a coincidental overhearing in a city with global tourism. Perhaps providentially carried past a devisement of some kind. Philosophy of Mind teaches that we don't quite have the handle on the mental mechanism that we generally think we do, even with respect to physical actions. Perhaps this city exerts a peculiarly strong force, especially after surviving a rough winter in reduced circumstances.
It seemed impossible to turn around and inquire into the event. I'm not quite sure why that was. Perhaps I have sufficient freedom here in the writing, and had sufficient freedom abroad, but a different circumstance obtains in the city.
At any rate, Ulysses is free to ponder the Sirens, as his inner determination in any case won't affect the outer determination of the course already firmly set for other shores.