What breed?
He's fairly young, what are you feeding him?
Have you looked at his eyes to see if they are uniform, not deformed in any way?
If he's crested or has a poof, are feathers trimmed and kept from the eyes?
Have you moved your hand around his face to determine how well he can see?
He doesn't have a crossed beak?
He misses the feed/water bowls 5 out of 7 times - this does sound neurological. It may be that he has a genetic or developmental issue that can't be corrected since he has always been slower.
I would try extra vitamins just to see if that makes a difference. Try them for no more than 2 weeks. You can still give vitamins afterward, but give them a couple of times a week - especially if you see improvement. I would go with 400IU Vitamin E and 1/4 tablet human B-Complex. Give him a little egg or tuna daily for the uptake of E.
If he's struggling that much with food/water - he may be nutritionally deficient. For a cockerel/rooster, I would keep him on chick starter (unmedicated) or an all flock type feed for all his life. He may also need to be tube fed at least once a day to insure that he's getting what he needs.
