Buckman.....
Have you made any progress with your problem?
If you haven't tried this already it might be worth a shot but with anything like this is best to make sure you have a backup of all your important stuff.
Go to the Dell Support web site and find the section where you can downloand drivers. Should be here:-
You can enter your Service Tag number and it should pull up a number of driver options, one of which may be for you keyboard. Download it and install and see what happens.
The other option is within Windows find the Device Manager. On Win10 you right click on the Start Icon and it should appear within the list of options.
Run Device Manager and look for the Keyboard entry.
Expand the entry then right click on the Keyboard name and you should see some options to Update Driver or Uninstall Device.
Try Update Driver but if this says you have the latest version anyway ignore this and then try Unistall Device - Keyboard that is. Then reboot your machine. It should find your keyboard and install the latest driver for it.
Best of luck