Thanks to Arthur's assistance, the agreement went smoother than he thought.
Not only did King Uther decide to release Morgana, he even made an announcement to free Emery from all the charges related to the death of Sir Badgemagus and his knights with his position as the knight commander of Divine Order.
The announcement dictated that what happened at that time was a self defense and thus could not be tried.
Honestly, the decision made by the king bothered Emery, somehow. There was a hunch that made him believe this would become a problem later down the lane. However, after thinking it through, Emery just decided to accept this as a win for now.
The next thing that came as a surprise was the king's, or rather, Arthur's initiative to give him a title within the Divine Order. It was a recognition for his alias, Merlin, as a wizard.