Displacement revealing Voronoi Fracture pieces, before they break

[Gianni333]

I have 2 pralines that collide and breake to pieces. They are prefractured with Voronoi frature then put into an RBD Sim. 

I'm exporting them as an alembic and rendering them in C4D. They are polyreduced with Displacement at rendertime and this is where I'm running into an issue.

 

The displacement is revealing the edges of all the prefractured pieces before they break and also in the chunks that never actually break apart because of the constraints.

 

I tried merging all overlapping points both with fuse and clean after caching the rbd sim and removing manifold polys with the polydoctor node, but that won't remove most of them, probably because the pieces have already moved a tiny bit apart.

The issue seems to be the manifold polys though, because when I go in and delete them by hand in C4D the gaps between pieces are not visible anymore.

 

Is there some way of merging all pieces that havent breaked apart yet and clean up the geometry at every frame of the cached geo, so I can apply a proper displacement map?