This seems as a very poor tactic if that pig pretends to keep good relationships with the gold king. I mean, he has no means to get the stones save stealing them. But now that they were discovered, they won't be able to get more so easily. So when the king demands more and he is not able to comply, he will be in serious problem.
All this looks like a plan to get a quick buck and then dissapear. But I'm sure that this pig was an important merchant famed for being one of the few allowed to meet with the king, so it doesn't seem likely he wants to burn that connection.
We'll see how this continue from here.