Soften sherbet at room temperature for 15 minutes. Spread 1/2 cup of fudge topping on top of chocolate pie crust, place in freezer for 15 minutes. Place remaining 1/2 cup fudge topping in microwaveable bowl, refrigerate till serving time. Spoon and spread sherbet over crust. Cover with plastic wrap and freeze for 3 hours. To serve, microwave fudge topping until thin enough to drizzle. Garnish cake with whipped cream, fudge topping, and fresh raspberries.