Boolean Union Many Voxels

Hey,

I am creating a volume out of voxels and trying to use the merged volume to aggregate modules with wasp, I need the volume one piece with only outer faces. Boolean union commands fail both for mesh and brep, could anyone think of a way to solve this problem?

P.S: An approximate volume would also work it doesn’t need to be hundred percent precise.

Here the way to suppress duplicate faces

Dendro or Shrikwarp could also be a solution. But not mandatory here.

or with natives: