All of these can be questionable considering the number killed gets more ranged the further up it goes. Soviet-German battles often had a large number of civilian deaths, many by units whose sole purpose was to hunt Jews and communists (So pretty much every civilian in the USSR). Moderate estimates put the soldier (USSR only) and civilian deaths in Ukraine during WWII at around 7 million (~16% of the population), making 1/10 of the deaths in Ukraine at its largest battle not out of the question.
Btw. great quiz! :)