There's something to be said for the sudden inclusion of someone else. Of course, it didn't take out Howard, but it looked as though he was severely injured. And Eponine was dead or dying, and Draco still felt a good amount of self-satisfaction that he had helped bring both of them down to this, and still get away relatively unscathed. Entirely unscathed, perhaps.

He hesitated another moment, then smirked to himself and ducked back out of the building, leaving the three - two - of them to their devices. Maybe he'd hear a bit more cannon fire that night.