Oddly, the comminuted fractures to the skull were long post-mortem and didn't kill the woman. Deterioration of the tissue tells them that the killer lived with the body for at least six months. (I assume the organs and other squishy bits were also removed.) She noticed wire in the hand the skeleton had been put back together for ease of manipulation.
Brennan reports later to Booth that the flesh is odd because it is a homicide in which the killer soaked the skin and scraped away the fat to better preserve the body.
