It’s all too late ... now the conspiracy people have a raison D’etre ...
I don’t think that anyone who smothered him with a pillow would leave the pillow over his face. If I want to sleep after the morning sun comes up, I put a pillow over my face. It’s not like a good feather pillow weighs 100 pounds! I have no trouble breathing, and the Sun is kept out of my eyes. I do it almost every day! I’m still alive!
IMHO the man died of a heart attack in his sleep. Nothing strange about his death at all.