1)
Why does Hashem free them?
1.
Malbim: They repented.
2)
Are the ropes snapped?
1.
Radak: Hashem causes their freedom. He can enable them to escape, or put in their captors' hearts to release them, or other ways to be saved - "v'Lo Niskenu Alilos" (Shmuel I, 2:3).
