You need Arlene, that Shark Lady in the New Ark police station.
She will have a request in order to help you, cause a Riot, under the Don's home in a beggar slum, ask them to cause one, sleep and return to the beggars and ask around if a riot has started, if not go the the Gentlemen's Club, and look for the beggar.
Note that you have Arlene, on board when she asks to meet Fawn.