Populating a Mesh with 3D Voronois

Hello everybody,

I think I have a trivial problem but I cannot solve. I want to populate a mesh with 3D voronoi cells. In order to do this, first I populate it with points, then make a 3D Voronoi diagram from those points and finally intersect two mesh sets. Intersection is not working properly, as you can see in the figure. I tried converting breps (3D Voronoi cells) to meshes, then the intersection returns nothing.

By the way, I was working with brep geometries (like a solid sphere) and making a Solid|Solid intersection (intersecting sphere with 3D Voronoi diagram), but it is not possible to convert an stl to brep (at least for a detailed object) I suppose. Solid | Solid intersection was working perfectly, but with meshes I cannot figure out what to do.