@PlaceYourBetts that keyboard in Flame doesnt really do what you think it does. If I were a betting man, I’d bet that at the OS level on the Mac side your F13 and F14 are set to something stupid, like Display Brightness Increase and Decrease, respectively.
Head on over to System Preferences, Keyboard, Display, and make sure the Decrease display brightness and Increase display brightness are disabled.
Most of the time these things happen its a conflict at the OS level.