If you do not want the user to trust the UI on the laptop but only trust the led on the key, then the UI must be changed and instead of displaying a red/green s

If you do not want the user to trust the UI on the laptop but only trust the led on the key, then the UI must be changed and instead of displaying a red/green status in the UI, show the text "LOOK AT THE LED OF THE KEY". This way users will never be fooled by a hacked UI that shows a green status.