In the novel, they actually met the 2 knights outside the castle, who were fighting together with Wayne's party. Rare completely ignored Wayne while talking to the knights, so maybe that's why they cut it out.
Incidentally Rare found the layout of the castle too complicated to navigate on foot, so she left through the balcony (she can fly). Dias had the same idea, except he decided to tank the fall damage instead. An engineer ant will fill up the crater later.
In the novel, when Rare reached La Colline, the battle actually went on a bit longer, so Rare was just watching when flying mid air. No idea why this was cut, save page count I assume?