Oh, I believe it. In fact, I go further than you, I think, as I am a convinced universalist, to borrow words from William Barclay; I don't just think that everyone will have a chance to accept the gospel, I think that, eventually, everyone will. (Incidentally, the history of universalism within Christianity goes all the way back to the early Church Fathers, especially the Greek ones, and there have always been Christians who have taught the doctrine; it's an interesting subject to investigate if you're inclined and ever have some time.) Anyway, which LDS body is it that maintains the records concerning proxy work and, if you know, how might I contact them?