User blog comment:IamJakuhoRaikoben/Chapter 377 & 378: Imperial Wrath of the Heavenly Dragon & With Friends, Always, Review./@comment-5006572-20140330120600/@comment-7418318-20140330170602

In answer to the first post: Two reasons
 * 1) Carla was too hurt to fly both of them out (if she was even able to fly at all.
 * 2) Someone was needed to hit the detonation button.