My apologies, I'd misunderstood the afterlife as some kind of 'state of being' or different existence. If I'd known it was an animal, I'd have looked at things differently.The odds of getting one or the other of two possible results cannot be compared to the odds of whether something exists or not.
With any particular THING (animal, vegetable, mineral, or god) which we do not know to exist, meaning we have never seen it, we have never found it's footprints or droppings, and we have never observed it's influence on any events, the baseline assumption is that it does NOT exist, period. Otherwise we would go around saying, well, I think there is a 50-50 chance that dragons exist, and I think there is a 50-50 chance that the monster in my closet exists, and I think there is a 50-50 chance that I will fly through the sky tonight, and so on. Are any of the those reasonable statements of the actual odds? No, they are not, and that is why it is also not reasonable to state that the odds of there being a god or an afterlife or a superbeing are 50-50.