it doesn't matter.
the kit _must_ work at least on stock speed. (otherwise this woul indicate a serious and general problem with the jedec standard..)
the qvl is not worth much on asus board it seems - with the note "it's OC an therefor not guaranteed" basicaly you don't have any reliable information, even if they tested it on the speed as noted in the qvl.
in the end you can allways blame the "silicon lottery" when it's not working with intended oc spec.
This kit shows the Maximus X Hero on the QVL, this would likely work at XMP. https://www.gskill.com/en/product/f4-4133c17d-16gtzr