Sounds like the situation is a bit messy now, but typically when the game gets stuck loading songs, and doesn’t reach the songs list, there’s indeed a problem with the “songs.dta” file.
I am not 100% sure but I think at that stage, the game only reads dta files, which means that whatever is wrong with files inside the “songs” folder, it should not yet cause problems.
What is disconcerting, is that even a previously working songs.dta doesn’t help. I would double check that you really used a previously working dta file. Otherwise try creating a progressively smaller songs.dta by removing songs at the end, or even a single-song dta file.
If you have an editor like Notepad++ you can search for “(” and count, then search for “)” and count, and see if they match in number. You can also analyse your dta file using the Setlist Manager in C3 CON Tools.