The king, too, submitting to the trash command of Kaikeyi has perpetrated an act, just or unjust (he knows better), for which we are made to suffer so much. [2-58-27]
Or he might have thought he is the overlord and can do as he likes. (Or, he might have done this for fear of God) Otherwise, I do not see any reason for the abandonment of Rama. [2-58-29]