Cleaning the Voronoi 3D Geometry with Attached Towers

Hi,

I’ve been trying to clean this up. but I cant seem to figure out where I went wrong with the faces. I’m new to grasshopper, so I don’t have vast knowledge on my steps so far. I’ve been trying to create my shape similar to the img attached…does anyone know how I should proceed?

Also been trying to input 4 towers inside (where the gaps are) the voronoi3D geometry as well but don’t know how to attach/join them so that it look like its sprouting out of it. Please help.

voronoi attempted cube ting.gh (23.1 KB)
voronoi attempted cube ting.3dm (146.1 KB)
voronoi-cubes-3d-model-stl