I am thinking the Dark Prophecy item about "Again the seed slays ancient wrong" was not fulfilled. Ostensibly "the seed" is the Seanchan, though what ancient wrong they slew (again) is a mystery. I was actually hopeful that this would be resolved due to a possible throwaway reference in the ToM glossary about the Towers of Midnight. For some reason, BS or Harriet felt compelled to mention that according to an ancient legend, the Imperial family would return to the Towers of Midnight to right that which was wrong at a time of dire need. Note that the phrasing also said the seed should do this thing before the Great Lord comes, i.e. before the Last Battle.

I didn't necessarily think they would Travel to Seanchan, since RJ himself ruled out further expeditions to the Seanchan continent, but I would have hoped for a different, possibly metaphorical fulfillment. Instead I got nothing, unless I missed it, which seems strange since the author went out of his way to bring it up. Unless the entire thing was planned for the outriggers, which have been scrapped apparently...