It should be obvious that nothing the officers did nothing that was lethal - the guy died because he was a morbidly obese sack of crap who was dehydrated from standing around in the summer heat for hours.
Did any officer punch him? No. Kick him? No. Nightstick him? No. Shoot him? No.
One officer put a single arm (not both, which is essential for an actual chokehold) around his neck for about 4 seconds.
99.999% of people subdued using that method would have been just fine.
They picked a guy who was apparently diabetic, asthmatic, had high blood pressure, was more than 100lbs overweight, had a history of drug use, who probably had heat exhaustion into the mix.
All of those factors that you list should have made it easier to subdue him. The officers came with too much force for the occasion.
I am not saying that they intended to kill him. I am saying that if you can't do your job without accidentally killing someone, maybe you should be reassigned to a desk job.