Adding a "Roon Tested" soundbar to my "Roon Ready" Group?

Hi all,
Sorry for the amatuer question but i recently bought a Samsung Q990d Soundbar for my basemet and wanted to add it to my existing Roon Ready Group (which consists of Naim Uniti Atom HE with adams Tensor Deltas connected, Naim Muso, Naim QB).
It wont let me add?
It tells me “1 group cant be zoned here”
And i cannot see the option to disable “private Zones” aywhere?
Any ideas?
Thanks
Ed

The private zone is in the device setup.

However, you can only group zones of one kind.

The “Roon Ready” devices would be streaming via RAAT, where the “Roon Tested” devices would be streaming via Chromecast or Airplay or some other mechanism. My Roon tested KEF LS50W stream via “KEF streaming” for instance. I had to add a streaming device (RPi running RoPieee) that was roon ready and then connect the KEF to it in order to group the KEF with other Roon ready devices. Also due to the KEF only being roon tested the settings for the KEF zone when not connected to the RPi/RoPieee are limited, so I have no option for private zone for them. I think what you may see in settings varies depending on the device.

I am not familiar with Naim gear but is there a way to connect the soundbar as an output device from the Uniti Atom? Depends on your use case if this is a viable option or not.

Yes , I have a Samsung HW-K950 which has a 3 ring 3.5 mm audio socket that I run from the 2 RCA outputs on the Naim Uniti Atom . My cable length is maybe 2 m it sounds like the case here would be longer