This dreadfuI event puzzles and disturbs me. I cannot claim any expertise in fast jet aerobatics, but I have had experiences that I wonder might be relevant.
Naturally, experienced pilots speculate that if the accident pilot had become impaired it may have been due to G, or to some sort of oxygen deprivation. However, if I have read things correctly the fatal manoeuvre went wrong right rom the start, way before the onset of G.
There is something else that can do that; a Transient Ischaemic Attack (TIA) - (
https://www.nhs.uk/conditions/transi...ic-attack-tia/). This often referred to as a mini-stroke. A TIA is caused by a very small blood clot blocking a small artery in the brain causing various symptoms similar to stroke; the clot then dissolves (if you're lucky) to leave no trace.
I have seen three people suffer from this, their main symptom was confusion and the only one that was actually diagnosed at the time was a friend who crashed his car. He said he had no idea what had happened, he was totally confused, and so investigations were commenced soon after the event thus revealed the cause.