Imagine a bot that takes turns auto-conceding or letting the opponent auto-concede.
The first hurdle is how the bot will detect if it is playing against another real player, or another bot. This can be quite simple. Have each bot keep track of whether it is their turn to win, or auto-concede. The bot should only start games once a minute, based on an exact second time where everyone syncs their windows clock to the same time server. For example, if 20 players, some botting, and some not, all start at exactly, say, X:X:42, IE 42 seconds after each minute, just pure chance will lead to bots being paired up against one another quite often.
To keep it simple, the bot who auto-concedes should perhaps simply be the player who goes second and over time this will average out as 50/50 since you are randomly chosen to go first, or second. If the games goes on and the other player hasn't conceded, you are playing against a real player and the bot should concede at that point anyways.
Is this something that would theoretically work?