I see... so your less-detailed sphere would not actually be rendered, then? --It would just be the invisible base on which the more detailed sections 'ride'?
I'm not by any means an expert on such matters, but my initial feeling is that using the PolyChipOff tool to produce animation is not the best/simplest/most efficient way to go about it. It's really meant as a modelling tool... and I don't know how you might go about attaching the high-res sections to the low-res polys properly and controllably.
I would recommend you think about other techniques, such as splitting your high-detail poly object into many objects (as many as there are shards), and making them dynamic... or using a particle object with your high-res geometry pieces instanced to it to control the motion.
Sorry I can't be of more direct help. Good luck!
-Steve