In a shallow roasting pan, combine the Worcestershire sauce, green peppercorn marinade mix, and herb seasoning mix. Place the crown roast into pan, bone ends up. Wrap the bone ends with aluminum foil to prevent them from browning too quickly. Using a pastry brush or spoon, coat the entire meat surface with the sauce mixture. Transfer the pan to the oven and roast uncovered for 20 to 25 minutes per pound of meat, about 2 1/2 to 3 1/2 hours.
In a large nonstick skillet, saute the sausages until browned, about 5 minutes. Add the onion mushroom soup mix, vegetable broth, and golden mushroom soup. Stir in the thyme, marjoram, parsley, and croutons. Season with salt and pepper.
Remove the roast from the oven about 45 minutes before it is done. Fill the cavity with the sourdough dressing. Return the roast to the oven and cook for the remaining 45 minutes. Transfer the crown roast to a platter and replace the foil with paper frills.