I have sort of an idea for that, and I myself was agreeing with Chompy anyways.
Lucas and Cass wouldn't try to help because, well, they can't really convince the parents. Likewise, Hermes and other deities would explain why they couldn't. Lucas would then cover her own ass regarding the gift she gave Harriet by telling her to make some harmless claim about its origin (any claim better than what boils down to "a stranger gave it to me"). She'd feel a bit bad about it, as she'd feel the parents have the right to know, but it would be better than Lucas risking being accused of whatever two currently-emotional and paranoid parents could come up with.
Mind you, the "emotional and paranoid" is NOT an insult here: Anyone in their position WOULD be emotional and paranoid at that moment.
