By looking at the pictures, it looks as if whoever was working on the prop was working on the back of a blade and hit a void in the prop. Small voids are common in hand laid up props. When laying up a prop using CF tow, the voids are easy to see and can usually be minimized. The prop in picture is similar to the Mejzlik props in that the face was first laid up with CF cloth and then tow was used for all the remaining carbon in the prop. This prop also has cloth on the backside meaning that voids cannot be seen and could easily be that large. I've seen one of the props that Igor has been selling and the quality is top notch, but due to their construction, it is possible that voids could be present. In short, I wouldn't be doing a lot of modifying the blades. As they are, the chance of a blade failure are small, if the blade is as it comes from the mould and not modified.