Just so people not flying the B737 know, the procedure for a passenger evacuation is to extend the flaps fully (Flap 40) so that any one escaping via the overwing exits can follow the arrows and slide down the back of the wing.
However I doubt that the crew would have been able to extend the flaps any more than they already were as neither engine would have been running so there would have been no hydraulic pumps working. In fact I'm sure the hydraulic systems would have been severed with total pressure loss.
Either way, the flaps were staying just as they were before the accident happened.