Good move, Guildenstern. I don’t know what it costs him to say this. Is he risking his position with the king to confess it? We haven’t heard anything like that in the scene before but there must be some reason they wait for so long to tell the truth. Have they been specifically instructed not to reveal their purpose there?
Or is it that much more insidious censorship that was not explicitly stated but gets somehow internally implanted anyway. The kind where you control yourself in anticipation of something that you only imagine to be true.