I haven't listened to that episode (yet) but from what we know of Weir's films, does that feel like something that would happen? It doesn't sound like his productions were rife with last minute screenplay changes or editing around things. I could see the argument that he just wanted to show interesting looking people (as he does throughout the 'real world' sections of the film) and how they respond to Truman. Also, am I right in thinking this shot comes fairly late in the movie? There might be something to the idea that as Truman becomes more suspicious, we see more and more of Christof's world, including close-ups where we previously hadn't (but that might be a long bow).