How does Jurisdiction work for Zaun and Piltover?

If Jhin indeed goes to Zaun and "perform," why would that matter to anyone in Piltover? In the new lore they seem pretty close since that one piltie was in the alleyways of Zaun. But I'm sure the crime rate is moderate or high in Zaun. That said I could be sure theirs some sort of authority there.....Or is it tied with Piltovers? Ekko seemed to Recognise Cait as an authority in interactions(Regardless if it's just game play interactions.) Although we have no map of the new lore, I'm willing to bet that Piltover and Zaun sort of make on very big City, just with two parts. Maybe. I've seen playrs wonder what Cait and Vi are goign to do if Jhin does indeed does have a contract there. But I wouldn't be so sure whether to consider them an obsticle for him if they have no Jurisdiction there.