You can order a private autopsy. I don’t believe you need to give any information regarding why you are ordering it, but I’m unsure what you might be asked.
This is an article from the LAT, I chose that since you are in California. https://www.google.com/amp/s/www.latimes.com/archives/la-xpm-2008-apr-21-he-autopsyside21-story.html%3f_amp=true
Some highlights from the article:
Make sure the pathologist is certified in anatomic or forensic pathology by the American Board of Pathology.
Make sure the pathologist, not a technician, will perform the autopsy.
Ask your doctor, the funeral home or the local coroner for a referral. The College of American Pathologists ( www.cap.org) maintains a list of board-certified pathologists who perform autopsies on a fee-for-service basis.
You can ask the hospital to do an autopsy also, but my guess is you don’t want them to do it. If it is a teaching hospital they might do one automatically, but otherwise probably not since your husband was older and in bad health.
The article also talks about the autopsy might find undiagnosed conditions you weren’t aware of.
The LAT article is worth a full read when you feel ready to digest it all.
This is Santa Clara County Medical Examiner-Coroner website. https://www.sccgov.org/sites/coroner/Pages/mec.aspx