Preheat oven to 300°F. Heat oil in a large heavy-bottomed pot or Dutch oven over medium. Add andouille and cook, stirring occasionally, until fat has rendered and sausage has browned, 5 to 7 minutes. Transfer to a paper towel-lined plate with a slotted spoon, reserving drippings in pot; set aside.

Melt butter in reserved drippings over medium-low. Add celery, corn, leek, onion, thyme, white pepper, and 1 teaspoon salt; cook, stirring often, until softened, about 5 minutes (do not let brown; add a splash of water if vegetables start to brown). Sprinkle flour over top of vegetables, and cook, stirring constantly, until fragrant and slightly browned, 1 to 2 minutes. Whisk in seafood stock and bay leaves, and bring to a boil over medium-high. Add potatoes and remaining 1 teaspoon salt. Cover, reduce heat to low, and simmer until potatoes are tender and broth has thickened slightly, about 20 minutes.

Once potatoes are tender, uncover pot, and stir in cream. Return to a simmer over medium. Stir in shrimp; cook, stirring constantly, until shrimp are just cooked through, 1 to 2 minutes. Stir in lemon juice, Worcestershire sauce, and hot sauce. Stir in reserved andouille, and season to taste with salt and pepper. Ladle chowder evenly into 6 bowls, and garnish with Old Bay oyster crackers and chopped parsley.

Toss together oyster crackers, melted butter, and Old Bay in a medium bowl until crackers are evenly coated. Transfer to a small baking sheet, spread into a single layer, and bake until golden brown and fragrant, about 20 minutes. Let cool to room temperature, about 10 minutes.