A dash 8 has de icing equipment, and is certified for flying into known icing conditions. Ice would not have been a factor.
Actually the report I read said they retractedthe flaps, a real no-no at low airspeed. A wing can fly at a lower air speed with flaps then a clean wing; bringing them up may change a flying wing into a stalled one
Actually I find this whole incident unbelievable. Stall recognition/recovery is some thing a 5 hour student pilot understands.
I suspect they may have come in high on final, and slowed the plane excessively to save the landing, rather then execute a missed approach, which is going to climb power, flying in a circle and trying again.