Koel is pretty bad off, thanks to all of the iron she was tied with as well as the torture she's had to endure. She will want to try to fight other vampires when she is finally free - except she can't, since she is seriously injured. So carrying her off - as she futilely tries to tell her rescuers OH NO I CAN TOTALLY FIGHT KIDS COME ON BLOOD DEMANDS BLOOD BE NICE TO GRANDMA but she now has no voice to speak of and she can't really fight back anymore or really move - will be pretty easy. Its just a question of getting her out of the numerous restraints put on her!