Sure, when they can see them, but they already say that milady has come, the moment she enters, even when they can’t see her yet. Then again, I don’t remember Ferdinand entering the library without Rozemyne being with him, once she is the master, so that might account for that.

As for the friend or foe thing, I understood it as that only counting for the Sovereign Knights, because both the loyal and rebel knights (plus the disguised Lanzenavians) all wear the same capes. Dunkelfelger, Ahrensbach and Ehrenfest knights would have different capes and that is even pointed out about the Dunkelfelgerians… Then again, the royal family and loyal sovereign knights don’t know about Ahrensbach and Ehrenfest yet, so you have a point in that regard. If the loyalists see them carrying silver weapons, they might attack right away, without trying to determin whether they are on their side.

Or even if they know that they are enemies of Lanzenave, they might think Rozemyne decided to take the throne with her Grutrissheit. Who knows what kind of lies Raublut spread among the ranks, just in case.

Edit: I completely forgot something important. While the book only mentions scholars, Alstede, Blasius and Detlinde would also have attendants and more importantly, guard knights with them, who are also wearing Ahrensbach caves. So the friend foe confusion is in place for Ahrensbach capes too and only the Dunkelfelger and Ehrenfest capes can truly show that they are on the side of the loyalists, by colour alone.