During the boat scene near the end of The Usual Suspects, Keaton and McManus encounter each other in the engine room. It's clearly unplanned, since they both almost shoot the other.
During their conversation, Keaton says:
There's no coke...I've been in every fucking room. There's nothing!
The next scene shows Arturo Marquez, watching as the door to his room opens, and a crewman falls dead in front of him. Presumably, Keyser Soze has found his target, and executes him.
Obviously there could have been coke hidden in the room where Marquez was hiding. So Keaton must have missed at least that one room. It's likely he missed other spaces too, since the crewman appeared to have been killed just prior to the door opening.
Why does Keaton claim to have searched the whole ship?
Is this a continuity error in the movie, where the scenes are just ordered incorrectly?
Is this an intentional error in Verbal's story that's supposed to give us an early hint as to the story's veracity?
If it is a hint, did Verbal include it on purpose? Possibly to make it look like Keaton was lying to McManus, which could further reinforce Agent Kujan's belief that Keaton is Keyser Soze?