Line the bottom of a 9-inch springform pan with parchment paper. Arrange 6-7 oatmeal creme pies flat on the bottom, breaking smaller pieces to fill any gaps.
In a stand mixer fitted with paddle attachment, beat the softened cream cheese on medium speed for 1 minute until completely smooth and fluffy.
Add the brown sugar, granulated sugar, vanilla extract, molasses, and pumpkin pie spice to the cream cheese. Mix on medium speed for another minute, scraping down the sides of the bowl halfway through.
In a separate chilled mixing bowl, whip the cold heavy cream with an electric mixer on medium-high speed until soft peaks begin to form.
Gradually add the powdered sugar to the whipped cream while continuing to beat until stiff peaks develop. This stabilizes the filling.
Gently fold the whipped cream into the cream cheese mixture using a rubber spatula with broad, careful strokes. Fold until just combined, being careful not to deflate the whipped cream.
Pour the filling over the oatmeal cream pie base in the springform pan. Smooth the top with an offset spatula.
Cover the pan tightly with plastic wrap and refrigerate for at least 6 hours, or preferably overnight, until completely set.
Before serving, carefully remove the springform ring. Chop the remaining 2-3 oatmeal cream pies and arrange the pieces decoratively on top of the cheesecake.
Drizzle the caramel sauce generously over the top. Slice with a hot knife, wiping clean between cuts, and serve immediately.