My goodness, that’s a sad story. Our crew has a fairly different take on stuff: our ACW figures have stood in for Mexican troops at Puebla 1862, my Union figures have a western look about them but that doesn’t stop us from using them for Gettysburg or First Bull Run. We used 1812 Prussians for Crimean War Russians, Gardes Mobiles for 1866 Hanoverians, etc. At least we don’t use WWII figures or Normans and Saxons for our black powder period games.
As for ACW terrain, we often use a mat with the default terrain being woods and the few clearings painted in. I find that more important than the buildings being correct.
This too shall pass