The pneumatic tube systen in the Geographer's Guild (in the film) is an old legacy system kept out of sentimentality.
Noting that it's actually computer-controlled and obviously linked to some sort of database system, but is far too elaborate for the modern day when most organizations of that type would be digitizing their old paper and film records. It's also quite obvious that some of the computers on the upper floors the Browns are trying to use are still running a DOS-type interface so it's likely this system was installed in the 1980s (when such a system would have made some sense) and would be an unnecessary expense to upgrade wholesale. It's likely the tube delivery system is even older, as even with the advent of computers a simple index database surely would have been enough?The security guard in the Guild (film) is secretly gay.
Mr. Brown's Wig, Dress, Accent disguise as the cleaning lady surely wasn't that convincing to make him appear like a woman, surely?