Just the kind of thing I was talking about on another thread, Roger.
Thank you, Jaime, for reminding me of Philip Van Zant and the sad manner of his passing. He was an incisive actor, who rather soon declined into a lot of B-Pictures. He worked fairly steadily from the time that Welles put him on the movie map, but perhaps his gambling habit took the money.
As for figures in the background of the scene in the screening room, obviously Welles did not intend some of featured actors in CITIZEN KANE to be recognizable to the audience. The experts over at the magazine, Widescreen, may have an explanation. They claim that most TV screens and monitors are badly calibrated at the factory. The light level is set too too high, and as a result, we do not see movies as they were meant to be seen in the theater, and the stress on the electronics robs the TV set of several years in peak performance. They recommend carefully turning down the "brightness" and "picture" controls, while reducing "ambiant light" in the viewing area. Following their advice, and using CITIZEN KANE as my test film when working on the adjustment, I have put Joe Cotton, Gus Schilling, etc, properly back into the shadows, brought the black and white photography of Toland and Welles into to its proper perspective, and improved the picture of all the other films that I watch, whether monochrome or color.
When you have identified all the people we're not supposed to see in that sequence, you might try that.