If you noticed it, it was meant for you to notice.

What do you think it meant?

I personally did not notice it, but if I HAD, I'd probably be questioning it as well. But this is your theory, go wild.

P.s. you're probably on to something. Even if it's as simple as a tactic employed during the interrogation of witnesses. If you know they're guilty, one might appeal to their "humanity" by calling them by their Christian name. Conversely, calling someone who hides behind a title by their first name can serve as an informal "dressing down", meant to install fear and indicate "I know what you did last summer".

P.p.s. I guess I just gave away how I would have interpreted the situation, had I noticed. 😉 Now if I had to guess about my theory, I'd go with the latter meaning being correct.