Preheat the oven to 375 degrees F. Place a rack in the bottom third of the oven. Put the pie shell on a baking sheet lined with parchment paper.
In a large bowl, combine the berries with the lemon zest and juice, the sugar and instant tapioca. Stir together to completely combine and set aside.
In a medium bowl, mix together the flour and brown sugar. Using a fork or a pastry cutter, cut in the butter until the mixture resembles coarse crumbs. Mix in the granola.
Pour the berry mixture into the pie crust and top with the granola crumb topping. Bake until the inside of the pie is bubbling and the top is golden brown, 45 to 50 minutes. (If the top browns too quickly, cover loosely with aluminum foil.) Remove from the oven and cool at least 1 hour on a wire cooling rack before serving.
Combine the whipped topping and maple syrup and mix until well blended. Serve with the pie.