Assuming that in the UAL US world a Captain can allow a 'non-pax' to board AND over-ride security of baggage screening then the CSR needs hanging by the ***** - alternatively, the Captain!
There is no need to over-ride bag screening - the pilot requesting the jumpseat would have entered through the normal passenger route, and the bag would have been a cabin-sized bag screened at security in the normal manner. In the US, the crew (i.e. the Captain) have the traditional "perk" of granting the jumpseat for travel to other pilots (even from other companies, and without notice) who are commuting.