To Make the Lamb and Turkey Loaf:

Preheat oven to 350°F. Place oats in food processor and process until finely chopped. Add turkey, tomato, celery, egg, soy sauce, and Worcestershire sauce and process until blended. Transfer to a medium bowl. Place lamb in the food processor and process briefly. Add to the bowl holding the other ingredients and mix well with your hands. Place in a lightly sprayed or oiled 8-by-8-inch glass baking dish. Bake until firm, about 1 hour. Let stand for 5 minutes. Serve with Cranberry-Horseradish Relish.

To Make the Cranberry-Horseradish Relish:

Place all ingredients in a food processor and pulse until coarsely chopped. Let stand at room temperature before serving. Cover and store leftover relish in the refrigerator for up to 2 days.