I seriously believe it might be worth her going under sedation and for a truly rabbit savvy vet to check her teeth. It really does sound dental, but im no teeth expert - i'm only going on what i've learnt.
The vet is a rabbit specialist. Shes treated Lilly since the day i had her, she came with a uterine infection, then she suffered from muscle spasms which cause the head tilt.
Shes just a fussy bunny, she chewing and eating branches and she will start eating again when she wants so if it was teeth she would lose rather a lot of weight and not eat at all. I was just wondering about new ideas to try her on