The results of a serious bird event are usually much more complex than a reduction in efficiency causing EGT limitation.
Compressor damage will lead to a reduction (or elimination) of surge margin. The ability to select increased fuel flow would not help in this instance.
Much time is spent during engine certification in deciding the best course of action following bird ingestion, involving bleed management, throttle manipulation and so on.
In this case it seems that the ingestion event was so severe that the engines were overwhelmed. Overfueling would have served no purpose.
Aircraft are currently certificated against the most severe possible environmental hazards in terms of climate, icing etc.. Large flocking birds have only recently been recognised as a paticularly severe environmental hazard. The pioneering CAA paper was published in 2002, but I'm not sure if matters have progressed in the meantime.