@Juergen I have finally found the time to log a Feature Request, please see Make HomeKit/Nuki mapping selectable to enable users to trigger the “Unlock” command to the Nuki Smart Lock 2.0 instead of triggering the “Open Door” command for details.
@baze I hear you as well, and have taken into account your requirements as well - enabling the user to select the preferred HomeKit/Nuki mapping would enable everyone to use both HomeKit, as well as the Nuki App, as preferred.