Preheat the grill to high.
Place the broth, sweetener, tamari, Primal kitchen ketchup, vinegar, ginger, garlic, and orange oil, if using, in a small bowl. Stir well, then pour half of the sauce into another bowl and set aside for serving.
Season the chicken legs lightly with salt Place the chicken on the grill. Grill for 10 minutes. Baste with sauce. Rotate the legs and grill another 10 minutes. Baste with sauce again. Grill until the chicken is cooked through and no longer pink inside and internal temperature reaches 165 degrees F.
Serve the chicken with the reserved sauce. Garnish with lime quarters, toasted sesame seeds, sliced scallions, and cilantro leaves if desired.
Store in an airtight container in the refrigerator for up to 4 days or in the freezer for up to a month. To reheat, place the chicken in a preheated 375°F oven for 10 minutes or until warmed to your liking.