Beth doesn't need to know nobility to recognize a dismissal when she sees one. Giving the countess a nod in return, she turns to go.

Outside, a few paces away from the tent, she catches Rani's arm. It's better to do this here, now, than in front of the countess--she's sure of that much. "Thank you."

Even though this is kind of weird. She knows better than to say that part.