Photos were rejected due to quality issues

The first one is underexposed as shown in the histogram:

There is some clipping in the blacks.

Blurring the face of a person is not the correct way to avoid model releases. That is indeed a quality issue.

I would also crop the picture differently:

You have similar exposure issues with the second picture, and I would add more sky and crop some floor.

As for your third, you have noise in the sky, and you have some dark points that could be birds, but still, I would take them out:

The beech trees are a little light and could possibly be darkened a little.

This person should have been removed. Each of the images seems a bit underexposed in the shadows.