Step 2 is magical. While you have the area selected, use the 'Auto Levels' tool in Photoshop. (For purposes of demonstration, I'm using Photoshop to demonstrate these techniques). Most of what I do for these images is in Photoshop.
You'll notice that it reveals quite a bit. That's because there is a small amont of contrast in the selected area. Because we are confining the 'auto levels' to an area with a very small amount of differences, the program is able to exagerate those differences. By comparison, try using the 'auto levels' technique on the entire image. The results will be much less revealing.
You'll notice that the area is a bit pixelized. That's because of two reasons:
1. The original was a jpg, so there are artifacts.
2. The image processing is guessing at 'in-betweens' when exagerating the levels.
Not to worry though! This at least allows us to see what we are working with. It's rarely possible to be able to restore something completely, but we can certainly see a lot more than was intended. If you proceed with that frame of mind, you will be pleased with your results.
Try this with the first image I posted and see for yourself! It works!
