Article continues below advertisementFormer FBI special agent Stuart Kaplan has raised significant concerns regarding the investigation into the disappearance of Nancy Guthrie, the 84-year-old mother of Today show co-host Savannah Guthrie.In a recent segment on the Thursday, March 26, episode of Jesse Watters Primetime, the agent discussed several points of contention he has with the ongoing, baffling investigation.Savannah recently gave her first formal interview on the Today show, pleading for her mother's safe return and emphasizing the family's "agony.