That's my take on it. It's all going to point to Sandy Burglar's pants.
Berger knew he was taking a big risk and therefore there had to be something worth "dying" for, just what it is we will never know.
There are three minor player possibilities, as I see it:
Clarke, Gorelick, and Burgler.
Of course, the three big cheeses directing them all have name Gore, Clintoon, and 'Toon.