As of today the only match that is official for WWE Night of Champions on 9/21 is John Cena vs. Brock Lesnar for the WWE Championship.
The other match that is official is Sheamus vs. Cesaro for the United States title.
Other matches that are likely are:
Dolph Ziggler vs. The Miz for the Intercontinental title
The Usos vs. Goldust and Stardust for the WWE tag team title
Roman Reigns vs. Seth Rollins. That looks to be a placeholder match until Dean Ambrose returns.
Jack Swagger vs. Bo Dallas
Nikki Bella vs. Brie Bella