At the end of Yeesha's journey, you enter the correct symbols and she shows up with a long speech, She then gives you a linking book. You use it. Normally, she would appear again in a cut scene. She does not. Everything else from that point proceeds just right.
I went back to the dry cleft and entered the symbols again. I got yeesha's long speech and she gave me the book, linked, and again no yeesha.