Of course some people know who the drummer is.
As far as the auditions being filmed, that doesn't surprise me. For one thing, in making the decision, it could be very useful for the guys to be able to go back and watch the auditions again and discuss. And the technology being what it is, it is so cheap and easy to do it almost doesn't make sense NOT to film something like that. Plus, we know Jordan has become a serious video freak over recent years, so it wouldn't surprise me if the suggestion came from him (or if he just decided on his own to do it).
Now as far as whether or not we, the fans, will ever see any of it...I could be mistaken, but I doubt it.