I mean, the obvious answer is instead of trying to divvy the sovereign nation between them, they should have stood up for them and defended them when the Nazis rolled in. Barring that, they should have liberated them, then left them the fuck alone. Even a stopped clock is right sometimes, this comparison is pretty clearly silly. They weren’t lamenting the lives of Nazis lost in the battle to push them out of Poland. They were lamenting the lives of the Poles after falling under the Russian boot, after the battles were won.
IIRC, the biggest uncertainty is about the singularity. I don’t know if it’s still true, but my understanding was that the consensus is that it isn’t really a true point of infinitely dense mass. That is how our current models say it must be, but many assumed our current models are incomplete and that more accurate ones will show that it must have some volume. And given the extreme nature of them, any updates to our models might have some significant repercussions in other aspects of them too.