Voronoi Problem

Hey guys, I’m stuck at trying to open the bottom side of this mesh. The end product will be a small table lamp/tealight . Right now, the mesh is closed on all sides, meaning it would be impossible to place a light bulb/candle inside. Tried Brep|Brep and Solid Difference but no luck. Also tried using a surface with an open bottom, but it always gets capped. Voronoi keeps wrapping around geometry.

screen-scapture

Thanks!