Apple TV Harmony Remote choice

Setting up an Apple TV 4K. Which brings me to my question. In this particular room I currently use an old model Harmony 720, as my better-half has memorized the layout and doesn't like change if she can avoid it. The Harmony 720 can only be programmed with the old 7.8.0.0 software.
I also had on hand a Harmony One IR remote that works with the newer My Harmony software. I was able to get it programmed to control the existing setup plus the default Apple 4K buttons (even home button) but I am missing the advanced functions "Guide, DVR, Live TV, On Now" I also have on hand a Harmony Elite with hub in use in another room but I could borrow it. What I would like to accomplish is to get a Harmony working with Apple TV 4K including extra buttons. I even heard a "record" button might be a possibility. I guess what I am asking is can this be done with the older IR remotes maybe by enabling CEC? or do I need to use the Elite to get there?
All this is simply to demo an Apple TV as I already have a Shield Pro on this TV but the Harmony remote is part of the user interface as far as the Mrs. is concerned.