Add pork roast and water to a slow cooker. Cook on low for 4-6 hours.
When the pork is mostly cooked, drain the liquid and shred the meat.
Add soy sauce, Worcestershire sauce, minced garlic, and brown sugar to the pork and continue cooking on low for another 30 minutes or until meat is tender.
Meanwhile, make rice according to the package directions.
Dice onion, chop broccoli into bite-size pieces, and slice mushrooms. Heat oil over medium heat.
Add veggies to hot oil and sauté 5-7 minutes until tender. Add soy sauce and Worcestershire; stir until heated through and well combined.
Serve pork with rice, veggies, and watermelon on the side.