Autopsy found multiple abcesses in buttocks (ouch!). Believes this the cause of very hight fever before death. Likely caused by unclean needle(s). Negative for sepsis probably because of antibiotics given. Methadone in blood but in body ~ within 2-3 days. Three anti-anxiety drugs found in blood. Died of drug overdoses, not abcesses.
Therefore, if she died of Staph pneumonia, it was most likely administered by someone else. I wonder if the medical examiner performed cultures on the vials of medication which was injected. That might be interesting.
This woman was essentially well nourished, not in need of nutritional supplimentation and therefore should have had an intact immune system. Relatively speaking, fairly few well nourished patients, not immunocompromised, die of Staph pneumonia. Relatively speaking with reference to the general population, lots of heroin addicts (self injecting drug users) develope Staph pneumonia.