In a small saucepan, bring giblets and marinade to a simmer over medium heat, cover. Cook giblets 20 minutes, or until cooked through. Let cool; finely chop. Reserve 1/2 cup cooking liquid.
Preheat oven to 375°. Melt butter in a 10- to 12-in. skillet over medium-high heat. Add celery, onion, and chopped giblets and sauté, stirring occasionally, 2 minutes. Add 3/4 cup chicken broth, poultry seasoning, sage, and garlic. Lower heat to medium-low and cook, stirring occasionally, until celery and onion are tender, 20 minutes. Meanwhile, cut linguiça in half lengthwise, then slice into 1/4-in.-thick half-moons.
Put bread cubes in a large bowl and stir in celery mixture, linguiça, and parsley. Stir in 1/2 cup giblet cooking liquid and remaining 1 cup chicken broth.
Spoon dressing into a 4- to 5-qt. baking dish and cover loosely with foil. Bake 25 minutes, uncover, and cook until browned on top, 10 to 20 minutes more. Serve hot.
Note: Nutritional analysis is per serving.