[Moonman62]

The restraining choke was loosely applied and the duration and was negligible to cause such a death. Unless it crushed his throat, which it didn't from a cursory view.

The ME at this point isn't giving out enough information. When did Garner die? Was it sudden cardiac arrest, asphyxiation, or an asthma attack? Did his hypertensive disease cause an enlarged heart, which would have made him susceptible to ventricular fibrillation? Except for the conclusion, the ME is being vague.

[Theoria]

You can see another video from the store facing out where Mr. Garner gets absolutely zero help from the paramedics once his condition spirals down. They basically have him handcuffed while he dies in front of them without any medical assistance.