Well, I think I figured out what I was doing wrong. I'm almost too embarrased to say what I think I was doing wrong, but since I love to laugh in the face of humiliation, I'll tell you all
I never invited the opponent into the home (where the chess board is). I think because the person wasn't inside the house they were not given the option to play the game. Before, when I had the board outside, the option showed always up.
Anywho, I got my sim to play against the chess opponent, who I now think are vampires, they needed to be invited in before they can lose at playing chess to my sim!
Of course I could be wrong and it was just some glitch in the Sim's matrix that has been corrected.