In 2019 Utah based CEO of Tinker Ventures visited Silicon Valley for a two day seminar after which she called her family in what they described as an agitated state. She told them, it's all a game, a thought experiment, we are in the Matrix. That was the last they heard from her. Ten days later she was found dead in her rental car half a mile away from the seminar location.
https://www.sltrib.com/news/2019/10/12/police-say-utah-tech-ceo/
I have absolutely no knowledge of this case beyond OP's post ..... but
families are often find out about mental illness right after the suicide.
"Natural causes" means "not homicide or suicide". This could be "heart attack brought on by anxiety" - takotsubo cardiomyopathy.