New leads in the search for Savannah Guthrie's mom Nancy could help crack the case. Walmart has handed over purchase records for a backpack — believed to match the one worn by the purported kidnapper in doorbell footage. Cops are also flying a Bluetooth "signal sniffer" over the desert in Tucson, Arizona, in the hopes of tracking the missing 84-year-old's pacemaker. This comes as DNA on a potentially crucial black glove failed to match any FBI records.