Bring 4-1/4 cups water, salt and oil in saucepan to boiling. Add rice, and only one of the seasoning packets. Cover; simmer 25 minutes. (Can be made ahead to this point.)
Meanwhile, prepare grill or heat broiler. Season pork with remaining seasoning packet from rice.
Whisk vinegar, Worcestershire, lemon juice, mustard, salt, pepper and oil.
Grill or broil pork 5 inches from heat 4 minutes per side until cooked.
Remove cooked rice from heat; let cool. In large serving bowl, mix rice, beans, corn and green onion. Sprinkle with dressing, one-quarter at a time, tossing to coat the rice thoroughly. (Can be made a day ahead and refrigerated.) Serve with pork.