They shouldn't have been in the point of impact in any case, so the root cause was something way before the impact, and cannot be seen on the video. Above in this thread is a link with the ATC recording, in which the pilot gives incorrect readbacks, indicating a typical CFIT where they just assumed all is fine until the last second when they tried to maneuver out of this. Hence the obvious surprise. The video seems to show they hit something at the tree top or streetlight level after the last second pullup/dive/bank/whatever that maneuver was.