He actually emphasized his authority from the very beginning, but she didn't figure out the implied meaning.
He was indeed good at controlling something fully as long as he liked. He could achieve his goal by using human nature, which was mystical and more complicated.
And now he made it.
Controlling someone like Rosy, who followed his order and sent her back, completely believed what he said.
And also, those men who kidnaped her showed a sense of vigilance to her.
Irish failed to push him away, but she wanted to try her best for the last time.
She could only seek help from that woman, though Joseph might have deluded her.
Thinking of that, she might be willing to help her. If Irish were in her shoes, who loved a man, she must have been willing to help a woman beside him to run away.
The reason was very simple. A woman's desire to occupy something prevailed.
She would help her rival, so she could be together with Joseph.