“Vatican cameos” appears in The Hound of the Baskervilles in 1901. It is not a code from WWII unless troops were referring to The Hound of the Baskervilles. Otherwise, it’s a straightforward reference to ACD.
Thanks for the info!
Interesting point of reference (that is only tangentially related to the above); during WWII, the The Special Operations Executive (SOE) was sometimes referred to as “The Baker Street Irregulars”. Additional trivia; Sir Christopher Lee has been known to mention his membership in the “Baker Street Irregulars” (SOE) during the war. (For those who don’t know, Sir Christopher Lee has also played Sir Henry Baskerville, Sherlock Holmes, and Mycroft Holmes throughout his career.) And that’s my random WWII/Sherlock Holmes trivia moment.
Lady Karasu 