You definitely don't have a 50% chance of dying in the sense of "experiencing dying". In the sense of "ceasing to exist" I guess you could argue for it, but I think that it's much more reasonable to say that both past selves continue to exist as a single future self.

Regardless, this stuff may be confusing, but it's entirely conceivable that with the correct theory of personal identity we would have a single correct answer to each of these questions.