Interesting that your focus is post mortem. As I understand it, Michael Levin originally was just looking to see what individual embryo cells might be able to do if not surrounded by other cells telling them what to develop into. He (and the folks in his lab) have been trying to understand the 'toolkit' developing / regenerating cells are equipped with in order to understand the electrical communication between those cells. I'm pretty sure that whether those embryos survived the extraction of a few cells was entirely besides the point as far as they were concerned.