>Does that cause him to exist in a state of limbo until such a time that he is observed to be dead by an outside party?

he is either dead or alive, regardless of whether he's been observed or not, but he would appear to exist in a state of limbo to anyone who has not observed his current state.

here's something else for you to think about... if i offer you a deck of cards and ask you to choose any card, do you really have free will to choose any card in the deck? what if after you choose a card, i use a time machine to go back in time and tell myself which card you're going to choose?