"Good evening, Lady Dorothy."
As a part of the character, she greets her back. There is one thing she has made a resolution about and that is, not to let the transmigrated lady know that she had as well transmigrated to the villainess's body. She wasn't sure how her reaction would be, delighted or afflicted.
Revealing her identity early would be troublesome when she has yet to grab to what her expectation would be. When she thought about it, one thing she understood was that, that Butler did not reveal another person transmigrating to the same novel. If she knew, she would have come forward to look for her.
If Lucien plans to reveal herself to her to justify that she wants nothing to do with the empress or the harem thing, she needs to gather more information about Dorothy, a character that was never mentioned in the novel or someone, she missed remembering.