.......go back and reshoot the image....the face is really burned out and if there is no colour to retrieve, then, it's kinda hard to manip it back to the correct value of brightness and fleshtone.........
Of course the edit introduces some new issues. Seriously though, the guys face is too blown out. The best you could do is screen the shot to lighten the figures in the shade. They are under-exposed anyway. If you are really ambitious, you could clone the tone side of his face, flip it, lighten it and try to blend it in over the blown out area. If you are good with drawing, you can use the colour picker to paint back in some of the missing tones. But, imo, it's not worth the trouble to get decent results.