On the possibility of there actually being remains that could be retrieved, I would tend to think that what they may have found was bone fragments. Given the figures for heat intensity to which the craft was subjected, all the soft tissue and organs would have been obliterated. Bone and cartilage, possibly not. For the why not, crematoriums take a human body and reduce it to ash by means of intense heat. Granted, no where as intense as the heat of the implosion but the ovens run for a longer time to make sure that what they produce at the end is about 6 pounds or so of cremains and even then, if you were goulish enough to open the container, you would see small fragments of bone that had not succumbed to the fire. What they may have discovered is bone fragments literally embedded in the remmants of the wreck. Nothing all that substantial but forensic pathologists would likely have gone over all the parts that had been retrieved, just in case. Probably about the same degree of methodic investigation as might get used for a plane crash involving casualties.
Nick