Unless person Y doesn't want to share that info? If a close friend of person x gave away that info for example.
Then instead of saying:
Player A stopped and looked at Player B "You are sure of this? He plans to invade her duchy?"
"Indeed Player A. When he told me, I knew I had to tell you and get you to warn her, we can not afford another war" Player B responded
You could do:
Player A stopped and looked at the man, a man who had Player C's ear and confidence, "You are sure of this? He plans to invade her duchy?"
"Indeed Player A. When he told me, I knew I had to tell you and get you to warn her, we can not afford another war" came the response.
Or:
Player A stopped and looked his informant, "You are sure of this? He plans to invade her duchy?"
"Indeed Player A. When he told me, I knew I had to tell you and get you to warn her, we can not afford another war" the informant replied.
Although I will admit that this forces us to trust that people are not just douchebagging us and not taking it direct from RP w/e and actually ARE learning about this in a valid RP and IC way.