I'm pretty sure Saul will hand the drive over to Estes, but Estes will sit on it because it will directly tie the Veep to the unpublicized, unauthorized, drone bombing which killed Nazir's kid.
It will make Estes LOOK like the mole, but he's not the mole.
In my opinion, the mole is someone who we've seen around the show, but is not obvious like a Saul or a David Estes. Saul and Estes are too well monitored, in too deep for too many years, for no one to not have noticed any lies, furtive behavior, or the like, over the years.
In my opinion, it's probably this guy
Someone in the game enough to get all the classified intel, but off screen enough to not be on our radar. Yet, when (if) he is the traitor, it will hit us pretty good in the stomach. Because we've seen him interact with Carrie at the school where she was teaching. We seen him in the war rooms. He's the most likely candidate.
@ the ending. I thought it was gonna take a bit longer for Brody to be exposed. Looks like Carrie still not getting her job back after being right, I guess the writers are sticking to realistic CIA policy and protocol, I applaud them for that 
@ that nikka.
