Maybe if this bet would be had, there should be some sort of timeline for the bet. Like whether amazon will accept bitcoins by end of 2017. If the bet would go indefinitely then OP when never lose because there is infinite time that has been set as the deadline. Well, I am guessing that this bet is possible, however I am more inclined to amazon accepting bitcoins, because I think that's a big possibility.
It looks like you didn't read the first post clearly because OP clearly mentioned that Amazon does not accept Bitcoin by end of October means what your looking for the timeline is already set. But you didn't read the first post. Anyway, someone already confirmed that Amazon is not going to accept Bitcoins for now but in future don't know.