The puerile would be looking for the obvious. "He was drunk, and fell over and banged his head"
No wonder his family want to keep things quiet. There can't be much worse than being related to someone famous who dies suddenly in an abrupt manner.
He was 59, and a renown chef; not exactly a famously substance/stress-free job. Chances are he had some kind of acute brain injury either inflicted from outside or within. Either way, he's dead. It's a shame - he was the same age as me.