In this case I think it would be best to fnd an image from that shoot that has the (section of) background relatively unobstructed and less blown out, then transform and mask it to fit into this image. (Masking should not bee too hard as the hair seems to offer good contrast to the background.)
As it is now there seems to be very little useable information in that section, but maybe the RAW can provide more.
Thank you for all your suggestions.
I'm pretty sure he only shot those images in Jpeg format.
He's not really a professional photographer.
I can open it for him myself in RAW but not sure how to transform and mask it.