And what would happen to poor Bernan if the "offical" Navehan temple in Tashal found out about this. His life could become very interesting squeezed between to rival Navehan organizations.
IMPH Bernan has been playing too many sides of the fence for too long, but doesn't know enough of what is really happening around him. There are too many wheels within wheels for him to keep track of. Bernan expects a civil war at Miginath's death and is playing a game to ensure that 1) this really happens, and 2) he is in position to make a grab at either or both nearby Earldoms (Osel and Vemion) in whole or in part. He believes himself to be the legitimate successor of the Kingdom of Arwn and Darlen.
He knows that "Augurs" control the Pagaelin, but doesn't know that they're Navehan. They're Lia Kavair, in his book.
He conspires with the Lia Kavair to buy steel weapons, and also to market his drugs in Tashal, but isn't aware of any Navehan influence. He doesn't know that the weapons he is buying "fall off the wagon" of shipments bound to the Jarin and are already paid for by the Earl of Neph.
He knows about the "Navehan cult problem" north in Vemionshire, but he thinks that is just a charade of the Lia Kavair. He doesn't realize that this is a branch of the Tashal Navehans.
He has a son who is an acknowledged bastard, to which he has turned over much of the dirty work of dealing with the Pagaelin and Lia Kavair. He knows that his son is a brute and a bully, but he doesn't know that his son is an Agrikan and is under the influence of Panaga.
He knows that the Lia Kavair want a bigger cut of his organization, but doesn't understand the lengths to which they are willing to go to get that - bringing in the Tashal Navehans.
The Tashal Navehans have brought in "outside muscle" from Lythia to investigate, but their operatives have already been turned by Panaga.
Bernan knows that Caldeth has been spying on him and has been spying in return.
The PCs know about the "arms-for-drugs" deal with the Pagaelin and know that Bernan, or maybe just his bastard (unlikely, because too much money is involved), are behind it but haven't yet figured out that the arms are likely Khuzdul-sourced.
The PCs have figured out that Bernan is skimming the proceeds from the barony that he manages.
The PCs have figured out that the drugs in Tashal are coming from Kyg.
The PCs have encountered the "Navehan muscle" from Lythia, but don't understand the Augur-Navehan connection or that there are actually 2 (or 3?) separate Navehan cults operating in this plot.
The PCs are only vaguely aware of the existence of Panaga.
The PCs suspect that the "agent of Caldeth" (the steward of the Caldeth townhouse in Tashal) whom they delivered from Tashal to Minarsas has some shady connection with Bernan, but don't know that he is a double-agent who was a linchpin of Bernan's Tashal operation.
The PCs have reported what they know to Caldeth about the arms-for-drugs and the Tashal drug sales as well as delivered "important papers" which document Bernan's shady bookkeeping. They don't know that 1) Panaga has an inside operative in Caer Minarsas, and 2) Bernan has his own inside operative in Caer Minarsas.
The gold mine is still a secret, for now.