Okay, so the trick for me was setting
I set it in the global Lutris “System Preferences” section, under “System Options” in the “Environment Variables” section. Now, as outlined earlier by others, this applies globally, and appears to actually get my gamemode monitoring tool to pick up gamemode daemon is operational. I did not have to toggle “Enable Feral gamemode” in the same section (global or per-game/app), it just did it anyways.
This is kind of silly, as really, I clearly have a working gamemode install, why can’t we just have Lutris pick up on that and allow the toggle? Instead of having to set an Environment Variable. This really is the original point I was trying to make.
That being said, thanks to those for helping me figure out a work around. IMO, Lutris should be updated to enable that easy toggling in scenarios like mine (where it is present).