It was just that, Ainsley was previously someone from a neutral camp, and even if she joined the dark camp in this war, she should not have such a deep feeling for the dark camp to be able to sacrifice her life so gloriously.
Not to mention sacrificing her life for the light camp, which was the enemy's camp.
This is why, Michael used the question to test Ainsley's current condition.
When in the brainwashing activity, the brainwashed victim would act closer to their hearts, and generally, they would not lie about their thoughts and feelings.
If Ainsley was still not as devoted as the other lunatic believers, it means that the brainwashing effect was still not perfect, and Michael would immediately strengthen the brainwashing skill once more.
However, Michael didn't know that someone could lie when they were in the state of being brainwashed, and their form was just consciousness.