[SkyPilot]

Two possible explanations is that they slowed below sufficient airspeed for an airstart or that for one reason or another they did not windmill the engine long enough before airstart to overcome rapid cooling brought on by the flameout at high altitude.

Quite possibly. I have done airstarts only in the simulator, but they were not that difficult. If you are at 41K, you trade altitude for airspeed--and it doesn't take Einstein to figure that out.

[rlmorel]

Perhaps they were too nervous to drop the nose to pick up enough airspeed?

Maybe they thought they should conserve altitude, etc. Who knows? I do find it telling that the last communication was at 9000 ft. It means they were probably panicking, and their brains were going around in circles.

I'm no pilot, but I have spent a lot of time around planes, and I know that In aviation, panic is a surer way to die than nearly anything else.