Baseball Prisoner's Dilemma

Inspired by this comic I was having a conversation with my co-worker Ryan, a devout Red Sox fan, about what it would take for him to root for the Yankees. I couldn't come up with a real scenario where that would make sense other than it being the last game of the season with a tie in records between the Rays and Red Sox with the Yankees playing the Rays for the last game. In that scenario, where the Yankees are already out of the playoffs, I imagine even a Red Sox fan could root for them. But, what if by some strange turn of events it was announced that there were going to be two World Series champions in the year 2022 (no idea why that year, but bear with me). As a Red Sox fan the choice would go like this: Either the Red Sox AND the Yankees win the World Series that season or it goes to the two teams the Red Sox fan hates after the Yankees (I imagine there's a pretty big gap in that list). It's sort of like baseball prisoner's dilemma. For argument's sake, let's say neither team has won a world series since their last and that years win will carry the same level of prestige as any other year. What would a Red Sox fan (or a Yankees fan, for that matter) choose?