There are two problems with this:
1. This is most likely some kind of advanced custom field storing the images as an array or object or something. There is no way for the plugin to find out how this is stored. However I might have a solution, but I don't think I can test it without FTP access.
2. The bigger problem is that I don't see any post images defined: https://i.imgur.com/S38NzHS.png
I also checked the Listings editor, but there is no “Post images” field to upload images: https://i.imgur.com/DEssgGZ.png
All I can see is the image gallery, but that's not the Post images box.
So even if I find a way to parse the “post_images” custom field, it looks like they are empty, so you still don't get any image.Best,
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