If you are giving Vitamin E and B-Complex daily, unlikely it's Thiamine (B1) deficiency.
Unfortunately it sounds like she's having more issues. Sometime when a bird has suffered trauma and they can become symptomatic from another illness. Marek's disease comes to mind.
I'd continue to work...
I'm sorry Stacy is not improving.
Marek's disease comes to mind. Unfortunately, I think you are doing what you can for her with home care unless you are able to seek vet care and have her examined and better suggestions can be offered.
Sorry to hear about your hen.
Do you have photos?
Good advice from @coach723 . In addition to her suggestions, I'd also start vitamin therapy to offer nerve support since she's suffered trauma to the head/neck. Give her 400IU Vitamin E and 1/4 tablet B-Complex daily.
Let us know how she's...