I don’t work for Epic.
I’m a developer like you.
I’ve seen this error on the forum thousands of times.
People usually solve it that ways.
Obviously the third option is not possible in your case because your game is already packaged and sold.
If they already updated the drivers.
The problem is probably in the nvidia panel.
I can help you find out exactly what you should do on the nvidia panel.
Just have to search the forum for the correct post.
If I find it I’ll post it here.