What version does you C61K show?
I had 0xFB7 (and still do) on my C61K mini's and had the same issue but my Genie was still running 0xD80 but once I got 0xFF3 on the Genie everything became consistent on the new GUI and I could then run the HDR test. My C61K is also connected to a 2016 LG OLED...