since she learned of her ability to start behaving like she did before Chelsea affected her relationships, at will.

Well, even if I'm right, it's not clear that Aro is likely to believe it. It is quite an inferential jump from "can talk to herself" to "can undo the effects of Chelsea's magic," after all, and we are not always aware of the implications of what we know.

Unrelatedly, but for example: it occurred to me the other day that if someone had told me a few months ago that we would soon be receiving the first confirmed signals from a technological artifact outside the solar system, I would not have believed them, despite that fact being trivially derivable as the highest-probability outcome of things I knew about.