I think I've kind of figured it out with the
RAY SWITCH node. I'll add a file...I've not stress tested it in a proper scene yet. The ray switch node is a bit glitchy in that you have to move the sliders round for it to register once you add it to the opacity channel.
It's nice because you can catch reflections on the floor while still lighting with HDRI. It's essentially ONLY visible to the camera but still gets lit by the HDRI.
I've added the file too in case anyone else wants to do this.
I know it's not realistic but I'm a motion designer so sometimes you just need to break the rules..I really want to try Redshift but haven't had the time to pick it up.
Thanks alot for the suggestions, I did try object tag first, but did;t think of the spherical camera idea, I did try that but the problem is you don't get any movement on camera panning..I guess you could add it to a sphere but it still looks a bit weird, definitely going to spend more time in that
Windows 10 | ASUS Pro WS X99 SAGE II | Intel Core i9-10900X | 64GB Corsair Vengence | 3x Evga GTX 1080ti