Photoshop :: Facial Tones And Neck/jaw Shadowing

I have a large picture that has ballpoint ink written on part of it. I had no trouble getting the background edited since it was basically the same color. I did end up cloning two different parts of the background and covering it twice to get a blended effect which worked great.

The problem is facial tones. There is ink covering the neck area on the left and the right and the head is at an angle. I haven't been able to pick a color or gradient that works. I tried to clone a different area of the face but that didn't work either. Then I zoomed way in and got each square (pixel?) to show up but it would take me hours to color in each one and there isn't any part of the neck that isn't covered in ballpoint ink so I can't even pick the right skin color/tone.

I downloaded a Gimp program but honestly since I don't know what all those tools are, I don't know which one to use to get it right so I'm hoping someone here can say "use this for this and that for that" so I don't have to trial and error each tool/effect.

Or, if there's another free photo editing program that's easier to use, point me in that direction.