Pris - thats a toughy................
The bottom left (at first glance) is pure 255 white, meaning theres nothing in there to grab hold of and change.
Sharon is totally right about dodge & burn and even selecting, but this one may be too farr gone.
When I get home, and have time, I'll have a 10 minute dabble with it - but my fear is the over-exposure is one step too far for a decent recovery.
Lets see eh!
John