Thank you for the update, I'm glad you were able to see the vet and have him treated.We wound up going to the vet on Thursday night and had good news! One eye was lost, but the other eyeball is still there! It's swollen still, but he had no other major injuries as far as the vet could tell.
We've been doing 3x/day antibiotics mixed in with the Harrison's Recovery food (a powder mixed with water) and pain killers 1x/day. I think it's helping! He seems to be improving but he is REALLY not enjoying the syringe-feeding.
Does he have any other injuries? Is his crop emptying?
Sometimes when they have had trauma it can take a little while for them to come around and eat.
Mare made a video of how to crop/tube feed, you may want to check that out. I would use a larger towel or cloth to capture the wings on a rooster.
https://www.backyardchickens.com/threads/need-to-tube-severely-molting-hen.1437023/post-23839502
How to crop feed.
https://www.backyardchickens.com/articles/crop-feeding.75454/