Auto-feather is normally meant to apply only to a prop's pitch setings while attached to an engine. The engine itself doesn't need to decrease its drag but does need to decrease the spinning power to the prop drive turbine (fuel chop)
The reason for auto feathering is to reduce the frontal drag against an engine that is no longer offsetting this drag with thrust.
The prop drag is way more than the drag of the non running engine missing the prop. My only question earlier had to do with the amount of increased drag in this incident from the obviously distorted cowlings.
Not much the pilots can do other than fly the aircraft and manage the yaw in a difficult approach phase.