I can imagine someone arguing that Google's fraud department defamed them, causing another department (the third party) to take actions that damaged the plaintiff. "unprivileged" might be hard to argue though.
Google talking to Google is not a third party in any sense.
In general, businesses don't need to do business with you and can exercise relatively arbitrary judgment on this. It gets scary when we're talking about entities with significant market power just deciding to exclude you, though.
