I beg to differ from all. I'm thinking along the lines of Birgitte... (Silver arrow). She is the only one I could think of who would help her.

This Sylvie woman helps her out seems all kind and comforting, obviously has an in depth knowledge of the World of Dreams since she shakes her head when Egwene confess she can't get out. Sylvie mutters something along the line of "Shouldn't be here. Dangerous if you don't know the rules". Then  perhaps most bizarrely after Sylvie sends Egwene flying out of the World of Dreams

We know that their lives are spun into T'A'R while they await either to be reborn or to answer the call of the horn. Furthermore in a conversation with Elayne, she said that she had broken the "rules" by talking and revealing herself. She also knows T'A'R as good if not better than Lanfear or Moghy, bacause she had been able to know of the forsaken's meetings and whereabouts without being previously detected (not to mention without the one power).

A possible explanation as to why "Sylvie" doesnt appear anymore is coz Egwene goes to the wise ones and doesnt visit T'A'R without any of the wise ones(in the begining) and after a while Moghy rips her out of it.

Just my opinion....