Use your mirror and you can see the natural answer. In the mirror push down on your cheeks and you will see how the marionette folds deepen around the mouth. Now, lift the cheeks and see how almost magically the fold are lifted up and soften. So the answer, use Voluma for what it does best, lifting the cheeks, to lift up and soften the marionette folds, and then secondly use Juvederm Ultra Plus to fine tune the folds for the most naturally looking correction.
Voluma is designed to be an ideal treatment for cheeks. Fortunately there are great fillers for marionette lines. I would recommend that you consider Juvederm Ultra, Juvederm Ultra Plus (a little thicker), or Restylane for that area.