Should I retreat her with the Valbazen? If so where do I get it?
No. Give your hen a liquid slurry of buttermilk mixed with finely chopped boiled egg. Use an eyedropper and put a couple of drops of the mixture on the side of her beak to swallow. You'll have to do this often until she gets her strength up where she can eat and swallow the mixture on her own until recovered.