If I, being a native German, can accept the topic and discuss it without calling people ignorant for no other reason than them disagreeing with me, why can't you? ...
... It's only natural and very human to feel so loyal but in a discussion one must attempt to put loyalties aside and remain fair and open-minded.
I put forward that the person who invented this what-if timeline was/is ignorant of World War II. Specifically, I meant ignorant of what Nazi's were. I'm not implying anything further, or trying to insult this person.
The Nazi government poured enormous resources into engineering technology to improve their military might and some of what they came up with remains quite impressive. Particularly in the area of rocketry. And I can well-imagine someone imagining about those impressive technical implications and what those machines would've been able to evolve into, from an engineering point of view.
However, this treatment of Naziism as a viable mechanism for governing a nation is where this person's imagine is in error. Nazi Germany was also pouring enormous resources into its death camps: the transportation of huge masses of people and the desposal of enormous quantities of corpses. This was a willfull, deliberate drain on the German economy, which was not robust, to begin with. There was a lot of "Creative Marketing" going on, just to maintain the illusion that it was.
Nobody else's opinions mattered to the Nazi Party, except for their own. And whomever was not of them was going to get humiliated, tortured and murdered, including (but not limited to) Jews, Gypsies, Homosexuals, the mentally challenged, the physically impaired, the weak, any and all dissidents (proven to be, or otherwise) and anyone they arbitrarily didn't like the looks of. That was their ambition and even if they'd won the war, the financial, logistical and physical drains on the german government would've simply forced The Fatherland to collapse into destitution and chaos.
The Nazi Party was not The Cardisassians, or the Klingons, or some work of fiction that had a future that could be played out according to an imagination without a rule book. If you're going to use this "what if" scenario on an actual party group, in this case, the Nazi's ... then you are going to have to play it by their rules. Especially, if the intentions for this exercise are trying to be sincere, at all.