Just trying to think WHAT could be wrong? Did you notice any symptoms earlier, like diarrhea, lack of appetite? Could they have gotten into anything they shouldn't have?
I wish I knew what to say -- its hard with little ones like that. In just the last year, I've had ones that looked good at hatch just go downhill, and ones that got sick which I sure would die perk up and look fine a few hours later. In particular, last year, I had one quail that had diarrhea and was droopy and falling over kind of like yours, and it was one of my favorites, sort of a cafe au lait coloration. I was sure it was going to die, but I did the warmth/electrolytes and tetracycline thing, and in about 4 or 5 hours it was back to normal almost.