I see NO reason why betfair couldn"t make a market in this.
All they would need is a list of "runners" & would have to provide
an "any other player" facility for late entrants.
We (the punters) would then offer prices to other punters on who we do/don"t fancy (in the betting sense!)
After all, they form a market for Big Brother & other nonsense !!
Not sure APAT members would wish to offer decent enough odds imo.
After all every player must be at least 50/1 ??
Some of us :-[must be 1,000/1