Preheat your oven to 375°F (190°C). Grease a 9x13-inch (23x33 cm) baking dish.
In a large skillet over medium heat, melt 4 tablespoons (half) of the butter. Add the onion, celery, and red bell pepper. Sauté for 8-10 minutes, until softened.
Place the crumbled cornbread in a very large mixing bowl. Add the sautéed vegetables, chopped parsley, and thyme. Stir to combine.
Melt the remaining 4 tablespoons of butter and pour it over the cornbread mixture. Add the chopped oysters and their reserved liquid, the milk, garlic powder, and black pepper. Stir gently.
Taste the mixture and season with salt as needed. Oysters and broth can be salty, so it is good to check first.
Pour the warm chicken broth and beaten eggs into the bowl. Mix with a spatula until everything is evenly moistened but not overly mushy.
Transfer the stuffing to the prepared baking dish and spread it in an even layer.
Cover the dish with aluminum foil and bake for 30 minutes.
Remove the foil and continue to bake for another 25 to 30 minutes, or until the top is golden brown and the center is set. A thermometer inserted into the center should read at least 145°F (63°C). Let it rest for 10 minutes before serving.