Stan was Leonard Rish's camerman who accompanied the reporter/terrorist to Wichita. The two later returned to Air Force One where Rish later got the opportunity to meet the President.
But to ensure his mission went ahead without a glitch, Rish unknowingly poisoned Stan with the same cobra venom he had used to kill Ray Trapp and Timothy Kerry which caused Stan to suffer a stroke and begin seizing in the Press Cabin on board the plane, resulting in the entire Secret Service agents being directed away from the President's quarters and the medical personnel also being called.
Luckily, NCIS Special Agent Leroy Jethro Gibbs caught onto Rish's plan and dispatched Secret Service Agent Caitlin Todd to cover the President while he went ahead to stop Rish. Gibbs tried to get Rish to surrender but Rish resisted, forcing Gibbs to kill him.
Stan's fate is unknown but it is presumed that as was the case with Trapp and Kerry, that he too did not survive the poisoning, resulting in his death.