It was spinning around in circles. Rockets don't recover from that. Anyone who thought the rocket might stay in the launch envelope is crazy.
Every second it spins is more test data. I would be surprised if they used the FTS.
Yes, but still, blowing it up too soon would mean collecting less data, and the more data you have to "debug" the issue that obviously happened, the better.
They want to gather as much data as they can for as long as they can as long as the rocket is inside the envelope.
There’s no need to blow up your science experiment until it’s actually a danger, even if you’re certain it will soon become a danger.
This could be the only flight where they get data on actual aerodynamic forces during a spin. It's crazy expensive to test that again so might as well make the most of it.