Persuasion/hyperstimulation aren't the only way. Maybe these can be countered by narrowing the interface, e.g. to yes/no replies, for using the AI as an oracle ("Should we do X?"). Of course we wouldn't follow its advice if we had the impression that that could enable it to escape. But its strategy might evade our 'radar'. E.g. she could make us empower a person, of whom she knows that they will free her but we don't know.