Just think about it for a second: she has no power, no strength, no allies, no money. Then a shady guy with a prominent role shows up and says, "Obey or else..." (and look as how the maid is afraid of him)
In real life, as a girl, would you just say "F** off"*? I don't think so. But you can build up your power/your strength bit by bit so you never have to say "yes" again.
That’s how I experienced and see the world — and that’s the perspective I want to reflect in this game’s story.
And she doesn’t acknowledge him as her master — she just lies to get through. It is also shown in the game after you chose this decision. (maybe I could add another option for the dom path, something like "Yes (lie)")