Thanks to another player figuring out how to get the DawnTrail Benchmark working in Lutris (I had tried a few times but failed), I have finally given it a whirl.
Score: 9011 High 1920x1080 Maximum DirectX11 FSR Windowed 12th Gen Intel(R) Core(TM) i5-12400F NVIDIA GeForce RTX 3050 https://sqex.to/ffxiv_bench_eu
If you just want the script to use its system/runner settings but not download the installer itself - download the official one then select it during the install process - which is what I did.