First of all, Chris, Windows+B gives the VK codes "91, 66, 91, 66".
To me it seems like the keyboard does not allow any other than certain keys to be pressed together with other ones. If I'm in the keyboard help and press, say, Alt+Control+Shift+K, NVDA will read out every key. When I add Caps Lock to that huge command, it will still say "AltControl+Shift+K", so it kind of just leaves the NVDA key outside the command. Exactly the same happens if I add Insert or the < key that Tyler defined in the Add-on.
I have looked at the manual driver page, and there are only two things showing up there: that Bios update you mentioned and then a rather inaccessible piece of software called Rescue and Smart Assistant.
I haven't been able to find anything keyboard-related to this machine. The keyboard drivers that show up in Device Manager are HID drivers.
The UEFI/Bios update may be of interest. I tried to install it, but I'm not sure whether it succeeded or not. Maybe I should try to figure out which Bios version it has now and whether it matches that newer one. The Exe file I found in the Zip file for the Bios update just seemed to do nothing and when I tried Install.cmd, the computer said straight away something like "press any key to continue".