The bet was already made, the details agreed upon. In your scenario if the dealer said "Yerp, whatever's on the window is whatever you're paying" and you hand o

The bet was already made, the details agreed upon. In your scenario if the dealer said "Yerp, whatever's on the window is whatever you're paying" and you hand over your $20 and they accept it as payment then yes, I would expect them to honor it. Would FanDuel void your bet if you misread the odds?