Cook the butter with the flour in a small saucepan over medium heat for 3 minutes, stirring constantly. Remove from the heat and reserve. With a cleaver, cut the turkey necks into 3 or 4 pieces. Heat the vegetable oil in a medium saucepan over high heat. Add the neck and the giblets excluding the liver. When the turkey starts to brown, add the onion, carrot and celery to the pan and cook, stirring often to brown the turkey and vegetables evenly. Pour the white wine over the top and scrape the bottom to loosen any brown glaze on the bottom of the pan. Reduce the white wine until the pan is almost dry. Add the chicken broth to the pan along with the rosemary sprig and simmer for 15 minutes. Strain into a clean saucepan. Add any juices from the turkey and return to the heat. Bring to a simmer and whisk in the butter and flour mixture. Bring to simmer whisking constantly to thicken. Lower heat to low and cook for 10 minutes. Stir in crushed cookies and serve alongside of the carved turkey.