Yes, towards the end we had some couples dancing to some romantic boleros. It just didn't seem like it would have been appropriate to throw on some mp3 of Cupid Shuffle, 80's hard rock, or Gangnam Style would have fit for this particular dinner part, even though the contact person made it sound like it was going to be a balls to the wall, high energy event. Like you say, you got to be ready for anything because they will throw you some curve balls from time to time.
Years ago a popular musician from the Jersey shore named "Crazy Hugie" gave me a hint as to why he was so popular. Mind you he really wasn't a good musician or singer but packed all the bars he played and had a great run. He told me "Know how to read your crowd"
Great advice and you did it at that dinner party. That's one of the things that experience brings. I've found people rarely know what should be played at their events, its up to us to read the crowd and react accordingly.
I've learned to be ready for anything. Congradulations on a job well done.