"Song Lan had a plan.
The task the Foster Family gave to him was to pick up a cargo from the Old Man Printing Factory before 21:15, which was foreseeable to become a lengthy errand run, just like those tedious side-quests in online games. Once he got the cargo, the Foster Family would inevitably direct him to deliver the goods to places labeled ABCD. At that point, every delivery point would regenerate armed creeps, setting up a destiny-filled duel for him.
He could not let matters develop in the direction the Foster Family anticipated. Hence, the best decision now was to accidentally lose the cargo.
This required skills and a convincing reason to make the Foster Family believe him.
If you mentioned that the cargo was left in the backseat while you cabbed home, not only would the Foster Family be unconvinced, but they would also think you are a perfect fool.
Therefore, in such a critical time, the heroic Director Lu must come into play.