One day if you care, I'd suggest up'ing the year to about 1925 rather than 1920 to better accommodate the events you are discussing; Hitler in his early days (Munich only happened in 1923 and he was released from prison at end of '24), fascism's being established (1920) and Mussolini in power by 1922 in Italy, Churchill's "wilderness", and the American's looming economic disasters.

That would also allow Versailles to be finalised, refused by the Americans (their own treaty with Germany signed in late 1921), the League to convene and have time to prove itself a disaster, and the effects on Germany to be felt.

Like any of these sorts of points, ignore them for the moment and keep the free-flow going.

I can archive the story as you write it here as well if you wish. Might be good "insurance". Your thoughts?