Murdered Mistress

On October 12, 1964, the day JFK's mistress, Mary Meyer, was murdered, Wistar Janney made two phone calls during lunchtime. The calls, each letting a friend of Mary's know she was dead, were made five hours before police ID'd the body. Peter Janney, however, recalls his father acting as if receiving the news for the first time by telephone at 8pm. How did Wistar, then a top CIA official, know who the victim was so soon and why did he pretend to suddenly find out hours later?