My idea of how this young man died from lack of oxygen to the brain is possibly way out in left field. I thought I would share it anyhow. I have sleep apnea and when I fall asleep in my recliner chair my head automatically hangs forward because I do not lay my chair back.
This cuts off the air flow through the trachea. I will wake up as if I’ve been in REM sleep after just a few minutes. I can tell my body is lacking oxygen and it’s affecting my brain. It makes my limbs quit working sometimes.
I do believe this young man could have been forced into a position for long periods of time with his head bent forward so his trachea prevented air from reaching his lungs. That is possibly why he died from anoxic brain damage.