I ended up abandoning all of this now that I have a Switch. I even found out that my fairly new 4k Denon receiver (no more than about 4 years old) doesn't have CEC or even ARC. So yeah I'm just staying with the Harmony remote.

On the plus side, the Harmony is great for controlling the Hue Sync Box I decided to pull the trigger on. It's awesome...

https://imgur.com/a/xUEPd8F