Do you think the color lemon in the neck feathers will appear later?
Yes. The chick is too young to tell right now. When neck feathers start coming in you should see some (not every bird is perfectly colored so the amount might vary), and they don't show their adult color before they get their first adult feathers, don't give up too early, made that mistake a few times when breeding Birchen (same pattern just different colors) back in the day.