No, Maomao suspects that the emperor's "brother" is actually his son that got switched at birth, but she doesn't know (or deliberately doesn't follow the train of thought that would lead her to the conclusion that) Jinshi is the imperial prince.I though that Jinshi already suspected that he was the son of consort whats-her-name (the manly one who looks much the same as him).
And I probably need a relationship diagram with all the names that just got mentioned.