As the title suggests, Lutris is requiring me to sign in to GOG so that it can verify my ownership of the game. If my memory serves me well, I used to be able to simply click on the GOG version and then link it to the installation executable file that I downloaded from gog-games.com.
I tried lutris, heroic, bottles… even steam has issues with dodi’s or FG installers. Now I just do wine path/to/file to install and add .exe as a non-steam game to run it through proton and it works every time.