Ron,

Good thinking, but I'm afraid I can't actually accept these bets. I'm pretty certain that bookmakers do not accept multis like that with more than one part of the bet riding on the same game. In other words, you can't have one part of the multi bet affecting another part of the bet. They've got to be different games. Sorry.

Perhaps you could wait until just before the game when you know the result of the toss and then back the team that wins it?