Still hoping for an answer on walking from Back Bay Station at night. The hotel's phone line actually has an option to hear directions from various directions and landmarks. But when I called, there was nothing about transit/pedestrian access from Back Bay or South Stations, which are major rail and bus hubs for the region. I was very surprised at the omission.

When I spoke to an employee, she said that I could indeed walk through Prudential Center, even after it closes at night. Does that match anyone's experience here?

I also suggested that they add walking directions from Back Bay to the automated message. She responded in a sort of, "um... sure" tone, but said it would be taken care of. I certainly hope it will.