One gets three wishes in Finnland, and THEN one has to pay. If Lanfear is anything like Mat, she might not have even realized she was making wishes when she said something along the lines of, "Asmodean betrayed me! Oh, I wish I could kill him for that!" Done.

After she took her three wishes, she would then have to pay, and she likely paid with her life. The only smart thing Mat did was ask to leave as his third wish, or he probably would have been killed and his skin used for clothes Silence of the Lambs style.

This easily explains the Cyndane body, the "attack of opportunity" comment and the clues being in later books.

By the way, I don't know why Fain is even on your list since Jordan explicitly ruled him out at a Question and Answer session years ago.