Preheat oven to 350F and set the rack in the top third. Prepare an 8x8 baking dish by spraying with nonstick cooking spray.
In a large mixing bowl, combine cornbread and crouton crumbs.
In a large nonstick skillet, add the sausage and cook over medium-high heat until browned, breaking it up with a wooden spoon.
Add butter, onion, bell pepper, and celery. Cook until translucent and softened, about 6-8 minutes. Stir in both sages, thyme, parsley, nutmeg, Old Bay, and salt. Remove from heat and pour into the bowl with crumbs.
Add Worcestershire, hot sauce, egg, reserved oyster liquor and stock. Stir together until evenly combined and mixture looks like wet sand (but not runny).
Gently fold oysters into the mixture and pour into the prepared pan. Bake until a toothpick inserted in the middle comes out clean and a digital thermometer reads 165F, about 35-40 minutes.
Remove from the oven, let it sit for 5 minutes, then serve and enjoy!