To dig in deeper with the errors, you will have to check the dependencies recursively, there could be some faulty dependencies causing this. Sometimes, built-in and DLC will cause these errors even though there are no errors. Check that all the DLC and built-in are up-to-date, and also none are marked modified. If you have any modified, revert to original.
I also found when I had this recently, that I had some corrupted assets that I had to download again from the DLS. These happened to be the Alco engines that were corrupted such as the DL570, or something like that. Downloading that again, along with some Australian locomotives that it's based on fixed a bunch of faulty but with no errors.