Heat grill to medium-low; lightly oil grates. Season chicken with salt and pepper; grill, turning as necessary, until lightly charred and almost cooked through, 15 to 20 minutes. Divide sauce between two bowls; one for basting and one for serving. Continue cooking chicken, brushing occasionally with sauce, until an instant-read thermometer inserted in thickest part of thigh (avoiding bone) registers 165 degrees, 5 to 10 minutes. Discard basting sauce.
Drizzle tomatoes with oil; season with salt and pepper. Serve chicken with reserved sauce, Macaroni Salad, and tomatoes.