If you haven’t seen the good video time lapse, the ship lost power, the lights came back up, the power went out again. Perhaps whatever caused the power outage the first time caused the backup power to go out also. The video shows heavy smoke coming out the stack, meaning there was probably max power trying to reverse the propeller and slow the ship. The port anchor was also dropped. Sounds like the crew did everything they could to prevent the accident.
Losing electrical systems would affect navigation systems and potentially rudder control. Obviously they still had engine control.
