R+L retelling and he's married to cassandra Baratheon so there's a reason to include them, valaena is betrothed to cregan stark and aemond has the empathy of whomever is in charge of dorne (idk, maybe they were also in a loveless political marriage) at the time so aemond is whisking valaena off to dorne and the tower of joy

Nobody thinks to look for valaena in dorne, which aemond also finds convenient for the fact that it’s a months long journey for Cregan to try to find her, especially since he stole her from the north,,,

Except aemond is ready for this war, nothing will keep him from the woman he started a war for and the children she will bear him