"Export all Images" not exporting small images

I have a large catalog I am extracting images from and most items have both a main and smaller detail image. All the larger image sizes export fine, but non of the smaller images are exporting. They are .png images. Any idea if there is a setting somewhere to adjust minimun image export size, or any other tricks for this? I am trying really hard to keep from having to manually extract hundreds of these. Any help appreciated.

Thank you.