At the very start of the original clip, I am not sure if you noticed but it looked like the mavic 3 was jerking about a bit. It corrected itself but that could be the 1st indication that something wasn't right. Sorry for your loss mate.

After being seriously disrupted, it stabilized for 1-2 seconds. This would seem to rule out a broken prop. Broken props can't temporarily recover. After restabilizing, its flight disrupted again only 1 second later. This would seem to rule out a bird strike. I can't see a bird striking it again a second time in only 1 second later. Large birds cant turn around and fly back that quickly. And I didn't see any feathers scattering into the air as I would expect from a bird coming into contact with the props. I'm baffled. What other options are on the table? The very first flight disruption spun the craft so quickly, so many turns, I can see that as electronics that malfunctioned. The motors do not have the thrust to spin the craft from a complete standstill, to that much instant high speed rotation. So that leads me back to thinking it was hit from behind, with a big bird striking it. Feel free to disagree with me and tell me your theory.

Apparently it was a left ESC failure. I need to wait for DJI.

Doesn’t look like a bird strike. Looks more like a failure