Yeah… Apex Legends dropped Linux support a while ago and that’s one of the reasons they cited; and tbf, there were publicly available Linux cheats that ran under proton.

But there’s also loads of publicly available “external” cheats that run the way you described. Some run through a virtual machine even. It’s just not a robust solution for preventing cheating, and mostly hurts the legit Linux players.

I’m sorry to hear you’re having trouble!

Regarding the vainfo thing, at least on Arch, the Nvidia vaapi driver is a separate package. I’m not sure what the equivalent is on bazzite, but that’s likely why vainfo doesn’t show anything. And you should still be able to use nvenc anyways, which sunshine will choose before vaapi.

Is moonlight able to see the computer on your network? And in sunshine’s web interface under the “troubleshoot” tab, there’s a log. Does it say anything that might help?