Most scrap veges are fine. Put them in a container and let them pick through, then throw away what they don't want.
I don't believe in stopping veges and greens. Stop processed foods like bread though if you are worried - moderation remember.
But then I am one who doesn't like feeding pellets because they are also a processed food! Mine only get wheat, a small amount of a mixed grain and free range as often as we can supervise (usually an hour a day and more on weekends)
I think your issue is just that they need a little more time. Check their combs and wattles. They'll get bigger and redder when they're close to laying. Two of yours sound close. Maybe you'll get an egg this week.
