Just tried V5 of the bios update just to see if it would work. Didn't work yesterday. Well, it updated something because rebar is enabled now. I had updated the OS to 21h1 today and right clicked on the exe, run as administrator. Bios version is no different.
MZ790A Bios 2002, GSkill F5-8000J3848H16GX2-TZRK, 13900KS, EKWB D5 TBE 300, Seasonic Prime TX-1600 ATX 3.0, Asus Strix 4090 w/ Optimus block, Phanteks Enthoo Elite, Asus Claymore 2, Asus Gladius 3, Asus XG349C, Samsung 990, Windows 11 Pro