The county coroner's report was technically true in a way meant to imply a false result.
Floyd didn't die from lack of airflow, he died because the knee stopped blood flow to the brain, that is the brain couldn't receive Oxygen despite the body being able to breath.
The county coroner carefully checked that Floyd could breathe, but not blood flow to the brain. Once asphyxia was ruled out (not really, since strangulation is not the only way to get it), the coroner was free to imply whatever was comfortable to the police.
I wonder how many other autopsies done by the same coroner were also misleading, and whether other cases will need a retrial.
The autopsy was purposely vague so as to give as much leeway as possible to the police.