The reason Kyran did not go after Gael when he escaped into his domain, the answer was simple: Kyran could not enter Gael's domain. It was easy for Gael to miss this important fact and only think that Kyran would react to killing intent. However, if Gael had considered Kyran's summons, he would have realized that if Kyran were reacting to killing intent, then he would have been attracted to the amount of killing intent from where his beasts and the army were currently engaged in a fight.
Alas, Gael was unaware that in Kyran's state, he could not distinguish between friend and foe and was purely reacting to any hostility directed at him. One could say that Kyran was like a puppet with only one program: to kill any hostiles around him.
So... yes, I am slowly revealing a bigger picture here. I wonder if you guys guessed it :D