Combine vinegar, curry powder and turmeric; mix until powders are well dissolved. Add soy sauce, oyster sauce, chili sauce and ketchup; mix well. Set aside.
Bring water to a rolling boil. Place rice vermicelli in boiling water for 2 minutes; drain, then immediately rinse under rapid running hot water for 1 minute and drain well. Toss noodles with 2 tablespoons vegetable oil; set aside.
In a hot wok or large frying pan, stir-fry shrimp and chicken in 2 tablespoons vegetable oil until just done, about 2 minutes. Add garlic, cabbage, carrots and tomatoes; stir-fry for 1 minute.
Add noodles; stir-fry 1 minute more. Add 1 cup vinegar mixture; stir-fry until ingredients are well incorporated, about 2 minutes. Add scallions, cilantro and sesame oil; toss briefly.