She doesnt have to as Geoff stated you asked the question Xiga answered that is all you get!
Your right, she doesn't have to in terms of game mechanics.
But what does she have to gain from refusing to answer?
1) Me thinking she is suspicious. Possibly others thinking she is suspicious
Thats it.
So, why would she want that?
There is no reason to refuse to answer the question unless you have something to hide, its that simple.
And you don't get it Noex, my plan isn't fullproof at all. It won't grantee us anything. Its just to make the lives of the Knight and Ace of Diamonds easier, thats it.
They have to put the dots together and nail a target.