I still think it is worth a shot to try it out if i can get my hands on some of the material without having to pay an awful lot for it.
What I believe could potentially happen is that, instead of separating the water, the Dodecahydrate simply melts under the pressure (and I was unable to find any densities for it at different temperatures).
Another idea I recently had was to use an inorganic acid, like 85% phosphoric acid, however, I was sadly unable to find any phase diagrams or density/temperature data for it. What I also couldn't find was the hardness of it (although I assume that there is a decent chance the crystals will be hard). If anyone has any data on phosphoric acid I would appreciate you posting it.