So the Lexerd screen film arrived today and I applied it to my iDrive screen with mixed results. The anti-glare scratches were certainly less noticeable, and invisible from some angles, but not gone. It also took me three attempts to apply the film, which rolled up a bit in one corner from taking it on and off.
The particular film I bought was Crystal Clear, and didn't realize until afterward that they sell an Anti-Glare film, so the surface was too shiny. Between the rolled edge and shiny surface, I removed the film.
I bought two more films, this time the Anti-Glare version, and will give it one more try ($37). If the Anti-Glare has a matte finish, and I'm able to apply at least one of the two that I bought without having to reposition multiple times, I think it will be a good solution.
If you have no chance of getting the dealer to replace the screen, then I think this is actually a low cost option to make it more tolerable.
Will let you know how round two goes!