Howdy Mo, I have cooked where they wanted the 1/2 chicken cut into 7 pieces also, a bit strange, but not unheard of. What I did was after the chicken is cooked, I removed the leg quarter and separated the leg and thigh apart. Then removed the whole wing, removing the tip and leaving the flapper and drummette together. Then cut the breast into 4ths on a diagonal or biased angle. This will give you 7 pieces that can be eaten and judged, the only problem is that the breast meat will start to dry out once it's cut. I would cook 2 halves in case a 2nd one is needed cause the first cuts didn't turn out as you would have liked them to....Good Luck with your cook.
Now if the rules don't state that all pieces have to come from the same half, then cook two halves and separate them into legs, thighs, and wings with the breasts intact.