Any chance of finding a wedge and a coat hanger around? The glass being frameless makes it fairly easy to pry back (being careful of course not to damage it or pop it off the track), and you should be able to at least flip the manual lock switch without too much trouble. That's what we used to do in the rental car biz when customers locked our keys in our cars

Hope that helps, although I'm sure someone will get here soon with better advice.