I have never encountered such error. Are you sure you are using an up-to-date mod version?
Yes, It only disappeared when I changed from 4.2 to 4.21
I also tried going to previous versions of the game it still won't appear
After deleting my save file I can actually select the mod in-game
Thankfully I was planning on replaying the mod anyways
Despite having the mod inside the Mods folder it can't be selected in-game 