"LBJ as a Navy Lt. Commander was awarded a silver Star."That awared was merely a participation ribbon for having inserted himself into a theatre of operations.
True, the plane turned back from the others due to mechanical problems, never came under fire, LBJ was merely a passenger, and no other crew members received anything to do with a combat mission, it was merely a plane that turned back from the formation and returned to base.
JFK never got a medal for combat heroism, in spite of his powerful father trying to get him the Medal of Honor.
He did ride a B26 on a bombing run in the SW Pacific. Since he was on a Congressional war committee MacArthur deemed it politically wise to give him a Silver Star.