Wash goat leg with juice of 1/2 lime, rinse, and pat dry.
Score and tie the goat leg to maintain shape while cooking.
Combine olive oil, garlic, thyme, parsley, oregano, rosemary, red pepper flakes, lime juice, allspice, honey, scallions, orange juice, and salt into a marinade.
Massage the marinade into the goat leg and marinate 2 hours or overnight.
Preheat grill for indirect heat at 275–300 °F (135–150 °C).
Place the goat leg away from direct flame on the grill and cook 2–3 hours, basting frequently.
Move the leg over direct heat in the final 15 minutes to crisp the surface.
Rest for 15 minutes before carving and serving.