I agree with others that he should be brought in. If you can put in eye drops, he seems like he could be a good candidate.
About development or being 'not right', it seems other ferals could potentially have this issue as well. Thrown out early with little socialization, plus lack of nutrition for proper brain development.
The feral on my balcony, Myul-chee, also seems a bit 'not right' in some ways. Wether it's nature or nurture, she has trauma issues, Which is one reason I decided to take her in, as we knew it was just a matter of time before something bad happened to her.