Prepare the Crust:

1. Crush the Cookies: In a food processor, crush the Oreo cookies into fine crumbs. Mix with salt and melted butter until the mixture is well-combined.
2. Form the Crust: Press the cookie mixture into the bottom of a springform pan to form a crust. Set aside.

Make the Cheesecake Filling:

1. Dissolve the Gelatin: In a microwave-safe bowl, combine 1/2 cup of the whipping cream with gelatin. Let it sit for 5 minutes, then microwave for 1 minute, stirring halfway through. Set aside to cool.
2. Make the Filling: In a large bowl, beat together the cream cheese, powdered sugar, cocoa powder, and melted dark chocolate until smooth. Gradually add the remaining whipped cream and vanilla extract, mixing until well combined.
3. Add Gelatin: Slowly mix in the cooled gelatin mixture, ensuring everything is well incorporated.
4. Assemble: Pour the cheesecake filling into the prepared crust and smooth the top with a spatula. Refrigerate for 4 hours or until fully set.

Make the Cherry Sauce:

1. Cook the Sauce: In a saucepan, combine cherries, sugar, cornstarch, and lemon juice. Stir occasionally over medium heat until the mixture comes to a boil and thickens.
2. Cool: Let the sauce cool to room temperature, then refrigerate until chilled.

Serve:

1. Remove from Pan: Once the cheesecake has set, remove it from the springform pan.
2. Top with Cherry Sauce: Serve slices of cheesecake with the chilled cherry sauce on top.