I think he died of an overdose of opiates. He was in a great deal of pain from 40 years of energetic performances and his hips and joints were as damaged as any athlete his age - worse because he did it in high heels. That he died in an elevator suddenly may indicate an OD. Or it can be as simple an explanation as a heart attack.
There is a long and involved article from a former drug supplier. He goes into detail about the drug use and how Percocet could have killed him if he was also taking other drugs.
I found the article to be weird. A lot of detail. Almost as if the narrative has been decided.