There is a different way you could achieve this. You could use KeyCode.Key.Value. Each key has an associated number to it that is built in. Why reinvent the wheel with a table when it already exists.
If you’re looking to return real numbers, the option is simple. Subtract 48 from any of the values and that will return a TRUE integer number representative of the Keycode. When you’re ready to convert it back, just add 48 to it, run string.char and then use Enum.KeyCode[whatever you string.char’d].
Dunno if that makes any sense.