This sentence is from the Wikipedia article about Michael K. Williams from "The Wire".
The scar led to his being offered roles as a thug in music videos.
As I see it, the word being is either a synonym for person, or it is an auxilliary verb to create Passive Voice. But in the case of Passive Voice, personally to me the word him would sound more correct than his: "led to him being offered". Can you explain this structure?