I’m happy to report that I’ve been able to fix my issue!
It went off an old steam community post by someone who had a similar issue. They mentioned they were able to fix the problem by deleting their Saved folder, and once I did so the fatal errors stopped. After some testing I found out the issue lies within the Logs folder, and deleting it is enough to make the error go away while keeping your setting intact. It may be that there’s a specific file within the Logs folder that is causing this, but I don’t have the patience to hunt it down, and deleting the folder didn’t seem to cause my game any adverse issue.
I’ve been able to play SP, MP, with and without mods, just like before the fatal errors arised, without a hitch.
You can find your Logs folder in “\Steam\steamapps\common\Conan Exiles\ConanSandbox\Saved”
I sincerely hope this works for everybody else who’s having this issue!