Are these possibly codes which include various insurance benefits as part of the negotiated discount? If so, the code-holder, e.g. employer, has an incentive not to cover people it does not control. More importantly for people who fraudulently use codes, it is all fine until it is not.
If there is a significant accident with real liability, e.g. where a third party is seriously injured, the first thing that will be checked is whether the driver fraudulently obtained the vehicle. If so, coverage will be denied under most policies.