The book was published in 1922. The law changed in 1923. This is as clear as possible, and Warner will lose.
My birthday is coming up, and if the decision comes out as I expect it to in time, then I'll record it myself, release it for free, and return it to the Public Domain so it can be used by whichever artist, filmmaker, business, or entity without the need to pay mechanical rights.
He does make this joke "the best XYZ money can buy" about governments, judges and police in europe and the US quite often.
The joke is old. I first heard in the early 90's, applied to government. It was old then.
I honestly would not be surprised if it could be traced to the early days of the Renaissance :)
The business with (possibly) mangling the PDF, however - I don't know whether that's perjury or perverting the course of justice or neither, but somebody ought to do hard time for that.
Which, of course, they won't.