The formal stance on Common - while it has some in-universe roots and references throughout the editions, is that it is the native language of the players/publication...
Thanks for that clarification, Niara. Useful to know.
That probably does mean my suggested fudge really won’t work. Ah well!
"You may call it 'nonsense' if you like, but I've heard nonsense, compared with which that would be as sensible as a dictionary!"