Who knows what the outcome would have been had he simply rested instead of going on stage. Don't work when you don't feel well. Even if you are literally non-replaceable.
They say he fell and hit his head and that's what killed him. Well, before the show he said he was having trouble with his hearing, among other things. Messed up ears messes up balance. He also hadn't eaten any solid food as he had a sore throat.
Don't work when you don't feel well.