Preheat oven to 350 degrees F (175 degrees C). Grease a 9x9-inch baking dish.
Bring the turkey broth to a boil in a saucepan over medium heat, and melt the margarine in the broth. Stir in the stuffing mix until thoroughly combined. Transfer the stuffing to a large bowl. Stir in pork sausage, ground beef, onion, and egg until the mixture is well combined, and lightly mix in the oysters, turkey giblets, poultry seasoning, salt, and black pepper. Transfer the oyster stuffing to the prepared baking dish, and cover dish with foil.
Bake in the preheated oven until the sausage and ground beef are cooked through and the stuffing is crisp and lightly browned, about 1 hour.
