Adjust an oven rack to the middle position and preheat to 350 degrees. In a food processor or blender, process cookies (including the creamy filling) until coarsely ground, about 10 pulses.
Continue processing until finely ground, about 10 seconds longer (you should have about 2 cups of crumbs). Drizzle in the butter and process until incorporated. Reserve 1/4 cup of the mixture for topping.
Use the bottom of a measuring cup to press the crumbs into an even layer on the bottom and up the sides of the pie plate. Bake until the crust is fragrant, about 10 to 12 minutes. Remove from oven and cool to room temperature.
For the filling:
In a large mixing bowl, combine the cream cheese, chocolate syrup and sweetened condensed milk. Set aside.
In a standing mixer fitted with the whisk attachment, whisk the whipping cream until soft peaks form. Fold in the chocolate mixture until no streaks remain.
Pour chocolate mixture into the springform pan and top with reserved crumb mixture. Cover with plastic wrap and foil, and freeze, 6 hours or overnight. Remove from freezer 30 minutes prior to serving. Store leftovers in the freezer.