Not possible. Any time an event such as the attack on the Benghazi consulate takes place the moment it is reported up the chain of command that automatically, and by law, triggers an immediate report all the way to the top of the chain of command to the Pres., VP, Sec. State, Pentagon and the CIA. And others.
Everyone was informed of the attack in Benghazi in real time. The President, Sec. State, the Pentagon, the CIA ... It's automatic, required by law and all logged.
Not to mention the attack on the Afghan base around the same time that took out so many planes and experienced people.