Rhazor was happy that the War Couple didn't make things hard for him.
He recognized their strength and knew he wasn't strong enough to take them on alone. So he used Ember and Nyrela to win their favor.
Not that he was required to do so. They, after all, owed him for the part they played in the death of his Beast Legion and so many innocent people. So his request was reasonable, and luckily, they had accepted it.
But then again, Rhazor had no idea that Ember had already called and issued a very strict warning to her parents before Rhazor arrived.
She had learned from Klaus that an incarnation of his was on his way to the Ancient Battlefield. So after her marathon with Klaus and her meeting with some of Klaus's wives, who were now her sisters, she called to tell them of what was coming.
So they were already prepared to face him. Luckily, Ember was very clear about her threat, so they had no choice but to accept what Klaus had requested.
