You can use wine to execute windows programs/the mod installer and steam has protonlayer for the actual game, RS14 is rated GOLD for linux - so it should be running smoothly.
You can see how to enable proton here.
I haven't actually tried doing this on linux myself, but this is how I'd go around getting it working.
Thank you so much for all your hard work, you've really made playing guitar/rocksmith fun. I picked up a guitar about a year ago and I've been jamming your charts ever since.