Ok, sorry. I expressed myself wrong. Should have said AGS, not HF team.
Believe me, I've been there. We had to redo almost every animation and model for BCoF because we did not know much about the period and research in general.
We wrote about that in one of our blogs: https://www.fsegames.eu/forum/index.php?topic=40157.0
AGS doesn't even know that there was no Prussian Empire and that Prussia did not have a "Kaiser", so I bet you that for them it is even more difficult to find the correct references, than it was for us in 2012.