I disagree. He didn't fail at trying; he just didn't succeed before the GPWS did.
Whether or not he should have initiated a go-around is subject to debate. It is a serious step to take when the Captain was allegedly the handling pilot, and was probably warranted in this case.
He didn't get the captain's attention back into the situation, he didn't do anything actually, regarding that matter. He also didn't successfully regain control of the airplane
timely: Given the case he had tried to take control, he failed to have to airplane properly configured to land, not just the gear, but the whole lot: flaps, autobrakes, spoilers (as per the report) and both also failed to fly the go-around in a proper way; there was nothing but chaos from the point they discovered the gear wasn't down all the way up to almost the missed approach altitude.
FO was PF by the way. He didn't fail at trying, he and the captain failed altogether at conducting proper CRM