The title says nothing about funeral directors diagnosing cause of death.
Go read it again and get back to me on that.
Funeral directors do not receive the medical record. Funeral directors embalm bodies and plan funerals. It was the same story a while back when the antivaxx conga line was breathlessly reporting clots like never before in bodies. It came out that the funeral director who has his 15 minutes of fame admitted he could not know the vaccination status of the corpse.
In the same way funeral directors are not privy to the medical record. This when the headline says Funeral directors who never had a 15 die from a heart attack now have one a week” is the diagnosis of the funeral director.