As far as I know, the only BC game that still registers as GOLD on the XBONE is Armed and Dangerous for the original XBOX. I've claimed almost every single BC Games With Gold over the last year (I had no interest in Stacking), *ON* my XBONE X, and they all register as "You own that"...except for Armed and Dangerous.
I know people started saying that you had to claim it on the website or a 360 when they had problems with Armed and Dangerous, but the very next game went through with no problems...as have every game since then. I think it was either some kind of licensing issue, or just a one-off glitch where that particular game registers the same as an XBONE game instead of an XBOX game.