King Harold Godwinson and the Witan Pled the Case Before the Pope

No one was there pleading the case for king harold godwinson. It's entirely plausible that normandy just whoops, let it slip their minds to notify harold. By accepting this delegation, in hearing the matter, the papacy was setting the precedent that the church had the authority to verify or deny a king's right to rule. They were sending a powerful message that all are subject to the church and that the ultimate authority and who has power in christendom was the pope. The only real claim that he had for this is secret promise that no one could verify. Even if william became king of england, he would hold his position under the authority of the pope