I don't recall seeing any threaded holes on the back of my FT-7900R fascia. I can confirm later when I get home if no-one else has confirmed this in the meantime, but from what I remember there isn't one.
The beauty of that plastic caddy though is that you could always fix a nut on the back of it to make it threaded and use that on the mount you wanted to use.....
Hopefully this shows up. Having some fun trying to upload an attachment on this forum.