Just send an email to the board of trustees / body corporate and move on.
That it is not aesthetically obvious, suggests it was drawn that way and not a mistake. Good typography is subtle and bespoke typography even more so.
To me the evidence in the article still suggests that “hard correctness” is probably not historically appropriate…hand lettering is not a typeface.
That’s really where I am coming from — the perspective of historical architecture, historical architectural practice, and historical methods of delivering buildings.
In particular, today’s mythological Wright is not the 1908’s historical Wright on a commercial jobsite. And the contractual relationships of a 1908 construction project were not delineated like current construction projects.