Preheat oven to 350°.
Crumble the cornbread into a large bowl; set aside to dry.
Cook the andouille in a big skillet over medium heat, just until the fat is rendered; use a slotted spoon to transfer it to the cornbread bowl.
Melt the butter in the same skillet and add in onions, celery, peppers, and half the scallions.
Cook until the vegetables are wilted, then add in the shrimp, garlic, and herbs; cook, stirring, for 5 minutes, then add to the cornbread.
In a separate pan, bring the stock to a boil, then pour half of it over the cornbread mixture; stir thoroughly with a rubber spatula and check the consistency.
Add more stock, as needed, to moisten the mixture (though it should not be soggy.
Season to taste with salt, pepper, and hot sauce, then stir in the remaining scallions and parsley.
Transfer mixture to a large baking dish, cover with foil, and bake for 15 minutes.
Remove foil and bake another 15 minutes, until the stuffing is heated through and the top is crusty and golden brown.