Abnormal objects that cannot be directly connected to symptoms are often identified in imaging. Your gliosis could be such. I have some abnormalities that do not relate to my symptoms.

Concussions do not often have focal injuries except for contusions near the skull.

Rather than trying to define whether your injury is permanent, can you choose to accept that your current condition is just that, your current condition ? Learning to move forward with your current symptoms will lower your stress and give you a better chance of improving. Research shows this to be true.