Heat the oven to 350 degrees. Combine the turkey, pork, ginger, oyster sauce and soy sauce in a large bowl and shape into meatballs. Place the meatballs, in a non-stick baking dish and bake, covered, for 15 minutes. Heat the oil in a skillet over medium-high heat. Add the garlic and sauté for 30 seconds. Add the carrots and sauté for 4 minutes. Add the broth and pineapple juice and bring the mixture to a boil. Lower the heat, add the pineapple juice concentrate and brown sugar, and simmer for 5 minutes. Mix the cornstarch with the water and add it to the sauce. Cook until thickened, about 3 minutes. Uncover the meatballs and add the sauce. Bake for 10 minutes and serve.