Do you think Brandon or Robert knew about Southron Ambitions? Besides Jon Aryyn, Tywinn, Hoster, and Stefon, who else do you think would have known? Their primary bannermen? Their maesters? Or is it too risky to let anyone else know?
The full scope? Probably not. But I think Brandon understood some of it at least, hence why he surrounded himself with friends from the Riverlands and the Vale as well as his fellow Northmen.
Thanks for the question, CrowzEye.
SomethingLikeALawyer, Hand of the King