In other words, 'we will let your client out of jail if we don't have to release the evidence to you'.
I don't see the autopsy results as being relevant to his case anyway. Those facts will be relevant in any wrongful death suits, brought on behalf of those killed, as well as criminal charges brought by the state for aggravated assault and murder.
The legal machinations relating to this event will be playing out for a decade, I'll bet. In the end, justice will be murdered.