When convicted bank robber Luis Marty Narvaez walked into the Far East Side Madison branch of Chase Bank on the morning of March 1, 24-year-old Charles Daehling was just weeks into his position as an armed, undercover security guard working without a state license and under contract to an unlicensed and now-defunct Nebraska security firm. Narvaez’s head and face were covered with a black cap and black mask as he briskly stepped to a window where a teller was already helping a customer, stuck a bag under the window and demanded money but never displayed a weapon, according to a...