... If you look at image #4 the strips on the girls top (around the belly) are in focus but the face is not. The camera has focused on the closest thing to it and with such a shallow DOF and the face on a diffrent focal plane (further away) and hence is not as sharp.
I do believe this is a focus issue and caused by the options in the camera set up. What we see here is the standard camera set up and it is not really all that helpful. I see it all the time when teaching students new to photography and doing close up work.