Read this:
http://www.poultrydvm.com/condition/thiamin-deficiency
That's what I read before I decided to treat my chicks. I gave the complex by injection, but you could give it orally too.
Before I even knew there was such a thing as wry neck I had a hen get it. I did not know I should give vitamins, so I just tube fed her and she eventually recovered, though she did end up with a slight tilt, lol.
Sorry she is not well. Recently I had two chicks with what looked like wry neck so I gave them shots of the cattle B complex and both were 100% better in two hours.
I also had two chicks with way looked like "crazy chick disease", those were treated with vitamin E and recovered in two days.
I...