Emery's Fey form specialty was speed and he was faster than Morgana in this form. So, when he shot forward to save Morgana, the old knight was surprised, making the old knight let go of Morgana and jump away.
Emery didn't chase the old knight right away. Instead, he got on one knee and checked on Morgana who had returned to her human form. Emery could see her chest heaving up and down unevenly, making it known that she was still breathing but in great pain based on her suffering expression. He then touched her bleeding side, which felt warm to the touch and had a deep cut.
