Good question! But, why did they need to interview Gavin if they had all the information they desired anyway...I mean, Satoshi went dark right around that same time so....Hmmmm.
It's the CIA's business to stay on top of world developments and Bitcoin certainly is one of those. You may as well invite one of the guys in charge of it to come over for a few beers to learn some more rather than piece it together from a bunch of whiners on Reddit.