Lews Famous Lobster Pot Pie

Name: Lew's Famous Lobster Pot Pie
Ingredients: 1 (3 ounce) package dry crab boil (such as Zatarain's® Crab & Shrimp Boil); 5 small lobster tails; 1 (15 ounce) package double crust ready-to-use pie crust (such as Pillsbury®); 5 tablespoons butter; 0.5 cup diced onion; 0.5 cup diced celery; 1/3 cup all-purpose flour; 1.5 cups chicken broth; 0.75 cup milk; 1 teaspoon seafood seasoning, such as Old Bay™; 0.5 teaspoon garlic powder; 0.25 teaspoon freshly ground black pepper; 1.5 cups frozen mixed vegetables, thawed; 0.5 cup diced potato