Hi and welcome!
I DONT have experience with this specific thing, but I'm going to throw in my two cents anyway.
Ten years ago, I got a case of Bells Palsy (facial paralysis). It's supposed to be temporary, but it left me with some nerve damage to the left side of my face. It's odd to be 34 and wake up with a different face than you've always had.
I still have some damage left over, after all this time. I'm very sensitive about it. To me, it's very obvious. I don't think anyone else much notices. Once, my husband said something to me about how I shouldn't worry about it and I had to tell him he didn't have to walk around with it on his face.
If her scar were anywhere else, I might try to dissuade you. But it's on her face. Never mind the teenage years ... fifth graders are cruel and middle schoolers are the spawn of the devil. I don't think you're being vain, no. I know your best interests are her well-being growing up. If anyone else says otherwise, well .... they don't have to walk around with it on their face.
Question: Is insurance going to cover this one?