I am pretty sure that I have read on BYC someone using brewers yeast as part of the feed.
Did a quick search and yes lots of threads:
https://www.backyardchickens.com/newsearch/?search=brewers+yeast&type=all
https://www.backyardchickens.com/t/97121/lets-talk-wry-neck-crook-neck
Here is one thread on wry neck. Wry neck sometimes is helped by vitamin e/selenium supplementation:
http://browneggblueegg.com/Article.html
click on left column article "crookneck"
Wry neck can be from injury, infection, or...