Cell Fracture fails every time

I’m trying to cell fracture some objects and every time, the objects mesh blow up into squares. I’ve tried recalculating normals and about every other fix I have been able to find. this happens on two systems with completely different hardware.

Please always supply a .blend file that illustrates the problem with any support question!
You could e. g. upload the file to pasteall and post the download link here.

If there is something wrong with the mesh, how are we supposed to ever find out with just a nondescript screenshot?