Looking at the video in slo-mo, the first stage did a great job despite the problem(s) that was/were occurring. It did not stop functioning until it blew up.
Nothing quite like flying in the middle of a ball of fire! Note the capsule had fallen free as seen about second 32 of slow-mo video, at one o’clock relative to the engines.
Report of continued telemetry from capsule at this instance.
First stage guidance & stability excellent considering compromise of structure-aerodynamics. From start to debris cloud 1:23 elapsed, yet retained orientation.
Worst case test scenario outside of pad event is Max Q for the Dragon crew version with abort system. The initial evidence of trouble from the video, is well past Max Q dynamic pressure flight point.