The numlock indicator is there because of the G80-5700, a numpad that was sold as an accessory to the G80-5000. Since it was designed to be paired with the 5000 keyboard, there are no indicators of any kind on the 5700 itself.
Not sure if it was worth noting but there are two versions - the original like you have with the function keys, and a newer one with two Windows GUI keys that have MX "Super Black" switches.
Also, I'm kind of surprised about your thoughts on the 5k switches. Vintage browns are among the best I've used except maybe vintage clears. Were your switches really scratchy? They're not supposed to be...I'll leave it at this, try a modern MX Brown keyboard, then go back and use the 5000...night and day
. You could also try to look for an 1838HPU, same switches as the 5000 but a bit more solid and integrated numpad. The split PCB of the 5000 is supposed to make that board have better feeling though
Either way, nice review, glad you at least got to try one