Sorry about that! Could you send me a screenshot of what your folder looks like with the DLC files? Hopefully I can figure out what's going wrong and help you fix it.
Thank you for that. From what I can see, everything looks as it should, which is unfortunate since it means I don't have an obvious solution now. The only thing I can say is to try to delete the game and do a clean reinstall. But I'll bring this up to your lead programmer and see if they have any better ideas. Sorry about that!