It is not bugged, just the lottery from hell. It can take a very long time to obtain one specific item off her, unless of course it is twine. Fieldbreaker I was literally going through the same until quite recently, and I hate to say that it took me over 7 months to grind one. Part of he problem is that her loot tables are full of superfulous items in addition to the Legendaries, such as bowls and iron bars.
As I state in the below thread, Funcom should consider 2 courses of action: I) remove the lower level loot from her loot tables II) reassign some of her Legendaries to the Green Dragon and the White Dragon, who have 0 unique drops, and as such no real incentive to battle them outside of novelty value.