Did you actually read the article? This part is particularly helpful in understanding what is being reported: Prince 'was diagnosed with AIDS six months before he died and refused treatment because he believed God would heal him'.
There is a significant difference between diagnosis and treatment. At the end of the diagnosis, the prognosis is determined. If this article is factual, he reportedly refused medical treatment. No effective physician will allow a patient to pick and choose what treatment they will accept and what they wont.
OT
Allow? Not sure about that. Who's working for whom?
Yes surprisingly: Life isn't a Burger King and you can't always have it your way.
As a business owner, I have fired a few clients, but not ones who have sense. Doctors, lawyers and bankers have forgotten who works for whom.
As an Engineer, I would gladly be fired on religious beliefs.