CptColumbo
Just One More Question
I can't be sure, but I'm guessing it had something to do with the fact people were a little preoccupied at the time and really weren't thinking about what they could do in that moment to ease the minds of conspiracy theorists 5 years down the road.
They were also short-handed as it was.
It would also be very dangerous to get that shot, and the FDNY and/or NYPD probably (IMO) deemed that the benefits of getting a multi-angle video of the collapse, did not make up for the possibility of losing more personel.

