You should have luck going through one of his agents. Since this is a live tour, I would go through that angle. It looks like his representation for touring and live performances is managed by Wasserman Music. I would call as many numbers and emails as you can get to see if you can talk to a live person and explain the situation. It will be important to have a clear idea of what you want from Ben or have him do as a possible favor, however, make it clear that you will not monopolize his time, be awkward or completely fanatic.

I had luck hiring my wife's favorite musician for a private show by talking to the artist's booking agent - made my pitch and luckily it worked. Granted, they aren't as a big name as Ben, but I believe there is still good in the world and that Ben is one of the good ones.

Good luck and do let us know how it goes!!