Let’s wait for an autopsy before jumping to all kinds of conclusions. If the guy couldn’t breathe he wouldn’t be able to talk or moan at all. Given that this occurred in the 3700 Block of Chicago Ave S., in Minneapolis, it’s very possible that the guy might have died of a heart attack due to a crack OD and stress. That area is a hotbed for drug dealing, prostitution, assorted other crimes, and murders.
You can talk while exhaling. But with someone's weight on your body, you can't INhale.