What does Harry find when she follows a small stream away from the hall of Luthe and what does she learn there?

She angrily leaves, and that evening, she quietly sneaks from the camp with Sungold and Narknon. Reaching the Hills by morning, she is surprised to find Terim and Senay have followed her, and although she tries to convince them to go back, they refuse and swear their allegiance to her. Senay further notes that some in her village will also join them, and that Mathin told them, days ago, what he thought Harry was planning.