So... What can I do? I tried some ideas on this forum, as well as others. But I'm starting to wonder something:
Part 2, the idea- I did not use the code for the add-on pack for my game. It corrupted and says DLC not found. Both of my friends used their codes, but also experienced this glitch in their games after days of playing. So this makes me wonder, isn't the addon just a code to unlock content already ingame? Well, maybe the game somehow thinks, through a glitch, that my save had the codes when they really didn't. Maybe someone with this glitch could get all the DLC add-on codes and download them and try to run their saves?
It's just an idea.
PS: I've seen some people I know from my past on here complaining, and if I add them up with the people I know whom have this game the percentage of people experiencing this glitch is not good. This is a major game breaker. So yeah, this was a half rant, half helpful idea. And last, my nearly broken laptop has issues with many forums, and tends to ignore my attempts to enter breaks, so I might have to re-edit and manually add them. I apologize now if that happens.