It's not controlling anything, just providing steering cues for the pilots along whatever route it's set up for. Setting it up for the flight's intended route is a checklist item, which appears not to have been performed on this flight. Also on the checklist is identifying the correct airspeed for current conditions, called "Vr," at which to "rotate" and bring the aircraft off the ground during the takeoff roll.

Actually doing that is a memory item, intended to be prompted by a "Vr" call from the pilot not flying. As far as I know it's not yet clear whether the PNF gave that call, but the PF certainly waited to rotate until well after reaching Vr. This is where the "sanity checking" appears to have failed, with the PF heeding the misconfigured flight director when it disagreed with other instruments and the situation visible out the cockpit windshield.