Broadsord of damnation in a bar?

Hi all. I got a question regarding our Bordertown burning champaign: skaven vs marauders are going to play the last orders scenario. Skaven Night runner hero bears the bradsword of damnation chaos artefact a twohanded sword essential to the campaign. As much as the artefact has a rule as:

Note that an Artefact of Chaos is much too important and dangerous to be left in the warband's camp or hideout. Therefore these artefacts may never be stored in the warband's stored equipment field but must be carried by a Hero (the leader in case of a Chaotic warband, see above). The only exception to this rule is the Tilean Merchant Caravan who may keep the item stored in a Trade Wagon.
And the scenario has a rule as:

Unarmed: All weapons have been confiscated for this game. Armour can be worn including helmets and shields. Miscellaneous equipment can be carried.

So does he allowed to play the scenario? Can he bring the chaos artefact? Also can he use it without proper skill and lacking from his weapon list? Does it count as a weapon regarding the scenario rule?