I was still getting the same error, even when trying to use GE-Proton to try and install the games.
However, I was able to get around the error by:
- Removing all Battle.net files
- Configuring Lutris to use GE-Proton
- Install the Battle.net launcher (which kicked an error at the end of the install, but still installed)
- Changed Lutris preferences back to Wine
- Launched Battle.net launcher
- Installed Retail and Cata Classic without any issues.
I tried to save time by using a backup copy of Retail, but it wouldn’t recognize it, forcing me to download the full game (RIP data cap).