Zhouzhou couldn't fly a plane, but Lan Tian could! And, most importantly, he actually owned a private plane, a reward from his superiors that he was allowed to use freely. Normally, he only flew it for official missions, but if Zhouzhou asked him? Well, who could resist her?
Besides, Lan Tian wasn't the kind of person who followed all the rules strictly anyway. Getting confined to a small room as punishment was routine for him, and it didn't bother him at all. If he hadn't been so capable, he would've been kicked out long ago. That's what his boss said, which shows just how much of a rebel he really was.
If Zhouzhou asked him to help settle things with Garen, that crazy guy would probably say yes and take her straight to Garen's hideout. After all, he loved a good thrill.