The best false flag is when the actor doesn't know he's in on it. See Snowden doing the things he's doing, let him do them with minimal restraint, and let the truth into the wild.

However, I don't actually believe it. This assumes competence above and beyond reasonable suspicion. It's much more believable that security was really just very poor. At some point somebody might have done a little less than possible to let him go, but that's about as much as I'm willing to believe.