Flipper, I wrote two articles on where the money could possibly go;
http://www.jehovahswitnessblog.com/2010/06/how-watchtower-organisation-could-hide.html
http://www.jehovahswitnessblog.com/2010/06/answers-to-how-watchtower-organisation.html
Just because they're a non-profit organisation, doesn't mean they can't hide cash.
Regards,
Carlos