Nothing. Despite the fact that it's completely impossible to envision any scenario where the Axis Powers might have managed to achieve victory, if it had happened, it certainly wouldn't have been the total victory that the Allies managed. If the UK, US and USSR had agreed to end the fighting on Axis terms, there's no way that it would have given them anything more than vast swathes of territory. There would not have been a full scale invasion of the UK, US or USSR, so the scientists would have remained safe, protected by the pair of oceans that abut the North American continent. The Axis wanted territory. And they didn't possess the air power, sea power or man power to defeat the UK along with the Commonwealth, the US, the USSR and other allies. Had the fighting ended, the Axis Powers would have been more than happy to maintain at least some of the territory they had acquired and wouldn't have been interested in engaging in suicidal acts like trying to invade.
The entire scenario is just completely ridiculous because the Axis never stood a chance to begin with.