Similar pages, different preview on Facebook

Hello, I’d like to try and understand why some pages on my site (same category, same settings, same template) are ‘viewed’ differently by the Facebook debugger.
On some, the image contained in the article is displayed correctly in the share preview, e.g.:
www.awand.org/interviste/silvano-agosti
www.awand.org/interviste/rachele-andrioli

On others, however, one of the images from the Mega Menu is displayed.
For example:
www.awand.org/interviste/dome-bulfaro
www.awand.org/interviste/wu-ming-2

What could be causing this?
I have attached screenshots of the plugin settings.
Thank you