I wouldn't drive two hours for antibiotic eye ointment, unless you see evidence of infection, meaning pus. Actually you can put plain Neosporin ointment in their eyes, anyway; a vet taught me this trick years ago. I don't know why her eyes are watery but I wouldn't consider it infection in itself. She may not need any eye ointment. I wonder if you got a bit of food in an eye; would be so easy to do.
It sounds like you have turned the corner with her; I certainly hope so. I wouldn't wait too long to start some regular chick feed, moist if needed. And I'd put her with the others at least part of the time, though she may need to be given food separately for a while, til she can compete.
Good luck to both of you.