Heat oven to 350. Combine the oreo crumbs and melted butter and press into the springform pan in the bottom and up the sides. Bake for about 8 minutes. Cool completely and reduce oven to 300 degrees.
For the filling:
In a mixer with the paddle attachment, beat the cream cheese and sugar on medium low until totally smooth. Add the vanilla and cocoa powder and beat again until combined, scraping down the sides as needed.
Add the sour cream and mix to combine. Add the melted chocolate in 3 parts, mixing in between until it fully smooth and mixed in. Add the eggs one at a time, beating in between. When the batter is fully smooth, press through a fine mesh strainer into a bowl to make sure any lumps are removed. Spoon into the crust and level the top.
Wrap the bottom/sides of the pan with two layers of heavy duty foil and place in a large oven safe dish. Place into the oven, then fill the outside dish with boiling water so that it comes about 1/2 way up the springform pan.
Bake until it is still jiggly in the center but set at the edges. I find that an instant read thermometer is the very best way to be sure you don't overbake and get that wonderful creamy texture you are looking for. The cheesecake is ready when the center is 145 degrees.
Turn the oven off, remove the pan from the water and leave just the springform pan with your cheesecake in the oven with the door cracked for 30 minutes to allow it to cool slowly which prevents cracking. Then cool fully before adding topping.
For the topping:
Combine all the ingredients in a small sauce pan and heat over medium low. Cook until the cherries release their juices and the sauce thickens up. Cool most of the way, then spread on top of the cooled down cheesecake. Place this in the fridge overnight (cover with plastic wrap once its fully cool).
For the whipped cream:
Combine the gelatin and water and heat for 10 seconds in the microwave to dissolve. Add the the cream/vanilla in a stand mixer and beat with whisk until stiff peaks are formed. Place into a piping bag and pipe onto the cheesecake.