This is an utterly unrealistic scenario.
It would have been in the military's interest to push for more democracy in the Reich government, since the people would have been conspicuously pro-military.
The German military of the Imperial Age was fiercly anti-democratic and would have never supported a democracy or a Republic. It did in the 20s to fight the communists, however the Kapp-revolt also showed that the military and the right-wing elite were never friends of democracy. Ludendorff (a right-wing activist in the early 20s) and Hindenburg (later President) were never democrats and as the victorious Generals of that scenario, they would been in charge and never implemented a democracy.
All the bad and strange things which happened in Germany in the 1920s are conventionally blamed on the harsh terms of the Versailles treaty. We forget, however, that the practical effect of these terms was really very limited.
This is also wrong.
The economic crisis of the 20s destroyed so much private wealth, that after the hyper-inflation, there was more or less a "clean slate start". People with "hard properties" (houses, territory, gold etc.) were in the advantage, others had just burned all they had ever saved. Maybe that didn't have too much influence on national economics, but it burned deeply into the minds of the people. Effects can still be felt today - if inflation rises above 2 %, people in Germany begin to worry a lot.
Weimar culture would have happened even if there had been no Weimar Republic. We know this, since all the major themes of the Weimar period, the new art and revolutionary politics and sexual liberation, all began before the war.
Also no.
Without the Weimar Republic, there would have never been an social-democrat-led coalition with a strong anti-democratic right-wing and a hardcore communist party as opposition. Instead, we'd have had a continued rule of emperor-appointed governments with centrist and right-wings in favor and a left-wing opposition led by social-democrats. The whole political landscape, that dramatically changed between november 1918 and january 1919, would have been preserved in the state of 1912 and progressed from that point on.
Therefore this statement is also wrong:
I would go so far as to say this: something very like the Nazi Party would still have come to power in Germany, even if that country had won the First World War.
The NSDAP thrived on national feelings of betrayal. The right-wing parties of the early 20s created this "legend" (Dolchstoss-Legende) that the left-wing parties were responsible for the defeat because they "stabbed" the victorious Army in the back. The whole political landscape from late 1918 to early 1933 was centered around this topic. The early right-wingers created it and the late right-wingers like Adolf Hitler picked it up to get votes.
A victorious Imperial Germany wouldn't have had that internal conflict, hence no such thing could have happened. Hitler would've come home as victorious soldier without the drive to become a politician.
The rest I also doubt...this is a very unrealistic scenario, all in all. Seems like someone just tried to implement all real-world events into his alternative timeline to make it seem "real", like this cold-war-attitude between Germany and the US and the emergence of a post-war-Nazi-party...