If Iah's view is correct, after the game, there will be at some versions of you who witnessed the Mets winning, some that witnessed the Yankees winning, and some that saw the game end in a tie. (As well as some for which the game was interrupted by aliens landing on the field and some where all the players spontaneously disappeared etc.)

So, subjectively, it'd still feel as if you'd gone to the game without knowing what was going to happen and then exactly one outcome (and not all outcomes) happened. But from a more objective perspective, all outcomes are indeed on an even footing.