I’ve seen this several times a year growing up on a dairy farm. It was usually with first calf heifers and bull calves. Some bulls produce larger offspring and recovery is iffy. Best to keep her up and on her feet as much as possible. If she lays to much, I’d be surprised if she recovers. Not sure what a vet will do other than give you a large bill.
Cows are tough though and I wish the best for you.
