The battle continued on while the mates of the defeated pack leader escaped for their lives. Sauron failed to kill the park leader. He then sent his warriors after the escaped mates with the intention of wiping out the descendants of the former park leader of the sharp tooth pack.
Ragnarok thought to himself in jest, "Fortunately, my father had the good sense to run. He may be weak, but he knows how to escape well enough or I wouldn't be born."
Sauron would have surely caught up to Cuthalin had he chased her himself. Then Ragnarok wouldn't have been born at all. Fortunately, pack leaders aren't meant to do menial tasks like hunting weak targets or hunting in general.
The Hunt for Cuthalin and the other mates was a move born out of anger. Sauron just wanted to punish the pack leader by killing his loved ones. He wasn't going to chase after them himself.