Make the worms: Combine the jello powder and powdered gelatin in a large bowl. Add the boiling water and stir until dissolved. Place the bowl in the fridge for 20 minutes, or until lukewarm. In a separate bowl, combine the whipping cream and green food colouring. Add to the jello mixture and mix well. Extend the flexible straws and insert them into a tall mason jar, flexible ends downward. The straws should fit snugly into the jar. Wrap an elastic band around the straws, then slowly pour the jelly into the straws. It will pour out into the mason jar as well, but don’t worry! Keep pouring until the mason jar is full. Place the jar into the fridge and leave overnight. Gently pull the straws out of the mason jar (this may take a little wiggling). Working with one straw at a time, run it under hot water, then squeeze one end and push the worm out onto a place. Repeat with the remaining straws, then place in the fridge while you make the cheesecake.
Make the base: Place the chocolate wafers in a food processor and pulse until they resemble a fine crumb. Add the butter and mix well. Press into the bottom of a 9 inch springform pan, then place the pan in the fridge while you make the filling.
Make the filling: Place the cream cheese in a bowl and beat with an electric mixer until smooth. Add the cocoa powder and sugar and combine. Then add the whipping cream, lemon juice and vanilla extract and mix until smooth. Mix together the gelatin and water in a small bowl and microwave for 30 seconds. Add the gelatin to the filling, and mix together with an electric mixer until fully combined. Scatter a few worms into the cheesecake pan, directly on top of the crust. Spoon some filling on top, then add a few more worms. Pour the rest of the filling on top and smooth the surface. Scatter 1/5 of the remaining worms on top, then place the cheesecake in the fridge until set, about 3 hours. Slide a sharp knife around the edges of the cheesecake, then remove the sides of the pan. Toss the remaining worms with some oreo cookie crumbs, until they appear to be covered in dirt. Sprinkle some more oreo cookie crumbs onto the surface of the cheesecake, then scatter the worms on top. Enjoy!