Are you using a smart phone for setup and controlling the hub? I have seen equipment show in the hub software without buttons, but I use the Pro Portal and do all of my programming in that program.

I was on vacation and where we stayed, they have two TCL TVs with Roku- I opened my Roku app and searched for devices. Try that and see if the model numbers are different from what you see in the Harmony.

I guess that worst case, you could call Harmony's tech support number or check their website's Community area for info.