A similar entry appears in the Wheel of Time Companion. Other information about the character is also included in the Companion, but we did not use it in the TarValon.Net Library.
Author: Atarah al'Norahn
Vayelle is captured at Dumai's Wells, and eventually swears fealty to Rand al'Thor. She is the last captive Aes Sedai to do so.
(Reference: Winter's Heart, Chapter 13).