@Granitefish It's obvious she gave them that quest so they could keep the sword. She was trying to help them grow. But since they are too dense to notice, she decided to go along with their charade.
@Eloyas maybe, but I don't think they are really dense. It might just seem more "obvious" to readers, but if I had (a new party after the betrayal and) accepted a quest, not sure I would have it wasn't a "real(?)" quest. If it's a real quest not sure they could just keep the sword, since someone could have really put it up, though.