So I finally got around to fixing a few things.
A few missing language prompts were taken care of, so that shouldn’t be showing things like “nations.ussr” any longer. I also removed the Heatmaps from the navigation menu on account of them not being updated anymore, so it was rather useless having them around.
It also turned out WG changes the language files with every release, the splitting of the Pz.III and StuG resulted in the translations for those tanks to be gone, but since the site still has “old” replays from before they were split, they showed up rather strangely. That got taken care of as well (hurrah!).