On boxes of Manischewitz Egg Matzos, you will find markings that say "Kosher for Passover" and also "According to Ashkenazic practice, all egg matzo may be eaten only by the young, infirm, or aged. If you are of Sephardic ancestry, consult your rabbi."
I assume since these say "Kosher for Passover" that the water and time restrictions were observed. I do not think they are chametz or kitniyot so what is it that makes them unacceptable? To be clear, I am not looking for an excuse to use them for the seder, I just want to understand the reasoning behind the restriction.
In case it is useful, the ingredients list says: Passover wheat flour, whole eggs, and apple cider.