Place ducks in a large pot, cover with water, bring to a boil and simmer for 5 -6 hours or until meat can be easily removed from body. Pull meat from body, roughly chop and set aside. Strain liquid into another large pot over medium heat, adding addition chicken or beef broth to make 3 quarts of liquid. Add Old Bay Seasoning and next 7 ingredients. Simmer until onions are translucent. While simmering, heat oil in a heavy skillet over medium-high heat. Slowly whisk in flour, stirring constantly until mixture (roux) is chocolate brown, but not burnt. Remove from heat and allow to cool completely before stirring roux into pot. Add reserved duck, okra, shrimp and sausage and stir. Simmer for 10 minutes.