(Review requested)

Welcome to OpenStreetMap and thanks for updating this. For the staff car park you already have access=private, to which you could add private=employees. It might also be worth adding disabled=yes to the staff car park, otherwise data consumers may treat the disabled spaces you've added inside as private (i.e. disabled spaces for staff only).

https://wiki.openstreetmap.org/wiki/Key:private
https://wiki.openstreetmap.org/wiki/Key:disabled