To you and me it may be clear as crystal, but it can always be argued that the there was a communication breakdown at a lower level. Actually, on some of the interviews (even on FOX) this is exactly what has been suggested by the reporters. That’s why the papertrail is important.
Not convincingly and not for long. When a Critical Incident Report is triggered (that's what happened when the coms officer in Benghazi called in to report the attack in the first 20-30 minutes) Every sit-room around the globe is instantly contacted and patched in to all communications coming from the source of the alert. That includes the WH sit-room, Pentagon sit-rooms, CIA sit-rooms, State Dept. sit-rooms, Eurocom sit-room, Africom sit-room and every other CentCom sit-room in the world.
When that alert is received the officer in command of the sit-room has 15 minutes to contact his superior officer. In the WH that is the CiC. In the Pentagon that is the Sec. Def. At the State Dept. that is the Sec. State. Every move, from receiving the alert to delivering the message up the CoC is fully documented. If the POTUS was not notified withing 15 minutes of that alert hitting the WH sit-room someone's head is on the chopping block.
Since both 0coward and Panetta were in the WH when the alert came in it is absolutely unbelievable that 0coward didn't receive immediate notice. Biden was there too and he would also be notified by his own liaison to the WH sit-room. That would be three separate required notifications that failed.