Interesting. I have a blown out backlighting shot from the 85mm 1.2 also, and it's great except where the hair gets raggedy from simply being "erased" in tiny patches by the overexposure. Otherwise I like the photo so much. I don't have my full setup right now for PP, as I'm remodeling and painting (real paint, latex!), so I haven't given it much attention yet.
My first thought would be to lightly clone in a smoother fringe using the other wing--while reversing the direction of effect in the Clone Tool's settings box. And probably fiddle with lightly smudging it...Or, just in LR, try using negative clarity along the raggedy part of the wing to mitigate the problem?
But I wonder if, in camera, I should be exposing less and more willing to lighten the skin tones in post. At low ISO's, not such a huge hit to IQ--maybe? When the sun is involved beyond true golden hour, hard to work with, for sure.
Were the two photos taken close to the same time? Or was the brighter one significantly earlier?