Just want to add: I had the Epic version. My saved games used to work, and it may or may not have been the DLC that caused an issue. However, I also upgraded my PC somewhere along the line, and my "saved games" directory had moved, and it must have been messed up in the registry. Other games have used it, but there must be something specific in the way Outer Worlds accesses it, and it stopped work.
Re-running the specific "save games folder" bat file (which creates the directory if necessary, and modifies the registry to point to it) did the trick! Saved me about 50 hours of play time (which frankly, I doubt I would have replayed) and can now enjoy the game!
Thanks for sharing the fix -