Cut pork and chicken into 1- by 3-inch slices.
In a 6- to 8-quart pan over high heat, cook noodles in 3 to 4 quarts boiling water, stirring occasionally, just until hot and barely tender to bite, 2 to 3 minutes. Drain well. Place the hot noodles in 4 or 5 large soup bowls.
Meanwhile, in a 5- to 6-quart pan, bring broth to a boil over high heat. Add beef balls and return to a boil.
Stir in shrimp, pork, and chicken; cook until shrimp are opaque in thickest part (cut to test) and pork and chicken are no longer pink in thickest part, 2 to 3 minutes.
With a slotted spoon, transfer shrimp and meat onto noodles in each bowl.
Season broth to taste with salt, pepper, and sugar. Ladle hot broth into each bowl. Sprinkle portions equally with green onions, cilantro, and preserved vegetables. Add garlic oil to taste.