See witness interview to Nashville bombing and lives at 166 2nd Ave N. I am sure it's been covered but since we see so much contradicting information, I am rehashing. From what she says she saw, you can conclude that RV was parked in front of the AT&T building. When you look at the damage of the AT&T building, you can clearly see the floor blown out inside the building. Perhaps one explosion inside the building and one outside.
Floor blown out inside Nashville AT&T building
My guess is the restricted air space is to prevent additional video of the blast site and clean up. Just seeing this damage clearly for the first time is quite eye opening. Juxtapose what damage you see with Mayor John Cooper's description and you notice fuckery is afoot.