Note that betfair has both an exchange and a sportsbook, and you linked the sportsbook. Their exchange market for this question is also called “next president”, but does have more detailed rules. In particular:
This market will be settled according to the candidate that has the most projected Electoral College votes won at the 2020 presidential election. Any subsequent events such as a ‘faithless elector’ will have no effect on the settlement of this market. In the event that no Presidential candidate receives a majority of the projected Electoral College votes, this market will be settled on the person chosen as President in accordance with the procedures set out by the Twelfth Amendment to the United States Constitution.
I’m surprised there’s nothing like that (that I can see) on the sportsbook.
Note that betfair has both an exchange and a sportsbook, and you linked the sportsbook. Their exchange market for this question is also called “next president”, but does have more detailed rules. In particular:
I’m surprised there’s nothing like that (that I can see) on the sportsbook.
Yeah, that’s still somewhat confusing, but makes it clear that they mean the election. I’ll edit to reflect that.
(I’ve now edited the original, mods please update—I gotta go and now is not a good time for me to learn how to properly paste the HTML or what not)