Hi Stuart,
Any logo can be uploaded into the WP media library on the admin site and used for markers. Perhaps they had added something to a child theme or added CSS. somewhere in the results layout. I have no way of knowing the WPSLP does not have have a repository of individual site images. That would be on their directory.
They would (I assume) have backed up their site or saved their CSS in a directory before making any changes
You can change the Results layout using html and css. And select or keep the plugin style that meets their needs
Docs about the CSS