Agreed. She even offered to sign a waiver for the picture. No dice.
The Atlantic article posted by @Riemann above talks about defilement of corpse laws. Your son may have the tools and skills and mindset, but he’s unlikely to risk his license over it.
All this talk of headlessness requires a theme song.
All this hinting at the skill needed to render a human head into a decorative piece leaves me baffled. Cut, twist, pop off, put in a big pot, cover with water, let simmer for six hours or so, let flesh fall off pristine skull. Even the brains come out in an instant by inserting a garden hose into the basal opening and turning the water on. Nothing to it, and certainly no medical school needed.
Does this occur before or after you call the mortician to pick up the body? Because either way, he’s going to report you the authorities for abusing a corpse, which is a crime in most states.
Oh, the irksome legalities are not my concern - I was clearly and only alluding to the medical skill aspect of the endeavour.