"Cuthbert" presumably is the name of the proprietor of "Cuthbert's Costumes." A fine individual with fine taste in tabletop figures. However, according to Buzzsaw, Cuthbert is a Warrior. Also, dead. This is only a mild conflict (I could imagine an old brain-damaged Warrior MIGHT start up a private business . . . ), but nonetheless one that goes counter to precedent. Randimar runs Randimar's Rarities, and Rusty Armor references "Randimar the Manyhanded" in a manner that suggests he/she does commerce instead of adventures. That's just fine. So might I suggest that the character in Buzzsaw be renamed?
Dorian might be able to give us some definitive answers on this. In the meantime, let's just assume Cuthbert ran a highly successful costumery, which then spawned a franchise of the same name. This would explain why there's also a Cuthbert's on Tournamentria. Circling back a bit, Kyburz of Kyburz Market actually owns an iron helmet, making him a much more likely target for Buzzsaw.
Is there something you're not telling us about leftover animosity for this former Irrational coworker?
what if it's his son or daughter that runs the shop now? they just didn't want to change the name out of respect for the father. and, because it's a successful and popular trade-name that people are actively looking for from all over the world.