One soldier thought that General MacArthur is lying, why is that?

General MacArthur and some of the retired soldiers were exchanging old war stories. General MacArthur mentioned that he led a battalion against a german division during world war 1. through brilliant maneuvers, he defeated them and captured valuable territory. After the battle he was presented with a sword bearing the inscription "To Captain MacArthur, Bravery and Leadership. World war 1. from the Men of Battalion 6. One soldier thought that General MacArthur is lying, why is that?