Rose stared at the door with a slightly confused, slightly worried expression. She was terrified of the Queen; she knew the woman would go to any lengths to get her out of here, including but not limited to dangerous means.
She wasn't surprised the Queen had already planted a spy—she had already thought of a few maids she had considered as the spy or spies. Welma had topped the list, of course, but she hadn't expected her to act this way when confronted.
So far, other than her impertinent way of speaking, she had not antagonized Rose or gone out of her way to make sure Rose was punished. However, Rose didn't think it was because she was nicer than Martha; she thought it was because there was a lack of opportunity for Welma to do so, as Rose never paid her any mind.