me too...heres what happened i believe,,..the idiot ate his heroin, had a seizure, caused his own demise.
Sounds like it may just be that.
You came to the same conclusion that I did. Heroin in large doses causes dfficulty breathing, convulsions, heart attack, loss of consciousness, and coma. Gray had every one of those symptoms. Convulsions in the back of the van and injury consistent with a bolt in the back of the van. Not hard to connect the dots.