Jackdaw with a head injury.... Help please

We have an injured jackdaw that has a head injury over its left eye. We cleaned the area with hibiscrub which allowed the eye to start to open again but it is bloodshot. "He" is happy to wander around the floor but isn't flying, just gliding. He also appears to have some sight problems - he walks into things that are light coloured. This is less so since his bloodshot eye started to open.

Obviously we can't take it to the wildlife rescue (avian flu), he has dried meal worms and 'wild bird seed' and water available. I haven't seen him eat or drink so we syringed agave syrup and water into him (about 1ml of each). He is kept in a dog crate when we're not home and overnight..

Does anyone have any further advice or suggestions to help us help him to either release or a happy life with us?

Thanks