I honestly suspect something took out a couple columns in the parking garage under the center edge. When you see the video of the collapse, you see the split second sag of what would be two columns wide then it goes pulls everything down like a demo when they kick the ground floor supports out.
Intentional bombing/sabotage? Maybe. But nobody claiming and let's face it, any intentional thing they'd be claiming. Columns corroded out so just the fa?ade is supporting? Maybe. Sinkhole? Have to snap the slab and I doubt the drop would be that concentric looking. Around here the columns in the garage are massive, the columns remaining in the photos look more substantially smaller. The remaining tower only has three across the short side, what happens if the middle one gets taken out?
The pedestrian bridge that collapse in DC was 65 years old and had been struck by a truck. The Florida U bridge collapse within days of being built due to design error.
