Every autopsy makes two findings-- mode of death (there are four choices here: homicide, suicide, natural causes and accident), and cause of death (more specific-- e.g., heart attack, gunshot wound, etc.). The autopsy report here starts with the finding "Mode: Natural." That means the autopsy ruled out homicide. Having ruled out homicide, the report doesn't have to say "I found no gunshot wounds," or "I found no stab wounds," or "I found no puncture wounds." Pathologists don't spend a lot of time listing what they didn't find.
What did the coroner decide as the mode of death for Michael Cormier, who experienced acute symptoms (indicative of a large amount of arsenic ingested about a half-hour earlier) and went to the dr’s office saying he thought he had been poisoned, was released (supposedly with a fatal-if-not-treated perforated bowel) and died of massive heart attacks with critical levels of arsenic in his body 2 days later?
Homicide, suicide, natural causes, or accident?