Onkel Willie, love your timeline. Great stuff!
I do feel, however, that the U.S. of A.'s entry into the war could have been handled more...elegantly.
Consider this: Up until OTL's WW I, German-Americans played a significant role in the US's daily life, many still spoke German at home and vigorously practiced German culture far exceeding wearing Lederhosen and gulping beer from big steins *g*. Many OTL German Americans anglicized their names during WW I as much to protect themselves from significant anti-German sentiment as turning their back on the old Fatherland for its misdeeds.
OTL WW II killed off whatever German-American influence had remained in the inter-war years.
As far as I could discern, no such event took place in your timeline. So, there could still be a lot of German-Americans who still aren't completely American and have strong ties to the old country. Throw in a couple of U.S.-Kaiserreich friendship organizations (nothing as sinister as the German-American Bund of pre-WW II vintage of course

) that, in concert with British-Americans (and maybe covertly funded by he Central Powers), start to lobby for entering the war on the Central Powers' side. They could form a volunteer unit funded and equipped by wealthy individuals that is sent to Europe and whatnot, start press campaigns against Russia and her allies etc.
Throw in a couple of VERY aggressively patrolling escorts in the Atlantic, trying to pick fights with the Russians and French ships and you might be well set on your way to the US allying with the CPs
And what of the US Jewish citizens' reaction upon learning of the genocide in Russia? A lot of potential there...
Just my two Euro-cents' worth off the top of my head though
