". . . I am a full realtor and can contact a lawyer, but she is not . . ."
What does that mean ?
Does she have a License; is she affiliated with the same Broker as you; is her P&S Contract Signed and Legal; WHY can't she or her Broker contact an Attorney ?
I'd be entertaining a suit for Breach of Contract along with her Buyers . . . . bearing in mind that the Sellers can't sell the place to two (2) Buyers; and you can't get blood out of a stone.
Why isn't her Broker going to bat for her (you said she's an Agent . . . . that implies that she's an Agent for a Broker) ?
Something seems to be missing here !