Any footage of damage to pentagon would / should be kept as tight as possible as it will reveal information to those who can use it as to the buildings reaction to penetration and the weaknesses and requirements to design any future attack. Building 7, landfill, insufficient structural integrity for the shock, simple, black boxes, the concentrated fire could easily have destroyed them, they're strong but like all human inventions fallible, grabbing all the data to hand on this I'm happy with who the instigators/driving parties were.