Your argument about the coroner saying what what the police want can just be applied here too. The problem was his death became politicized.According to this it was asphyxiation by compression to the neck
https://www.google.com/amp/s/www.nytimes.com/article/george-floyd-autopsy-michael-baden.amp.html
Regardless though his death should have never happened, they should have cuffed him, threw him in the back of the cruiser and called an emt.
The bodycam footage does somewhat hurt the prosecutors case, and trying to find a unbiased jury is another thing.