I've had some rather negative encounters with a few ORD lounge agents, so my advice is that you start the conversation with something like "I'm on an international itinerary in business class..." and then present the two BPs, not before, in order to prevent an impulsive NO when they see the Y BP. The point being that if the agent first says no it is sometimes very difficult to get them to reverse their opinion, even when presented evidence that they are wrong.