Actually it does.. but they only sell items when they're at the location listed above (X22-Y21). They don't sell items if they've been kidnapped in that FATE and are to the east of the highbridge in the Amalj'aa camp. If they're on the highbridge, then you should be able to buy these items.
There are 3 NPCs who have varying times that they sell items, and all of them depend on the status of nearby FATEs for whether they've been kidnapped or the area they're in being overrun with monsters.