Hi Ernest.
Thank you for taking the time to explain why the attachments aren’t recognised in the page or post.
I have found a workaround which might be really useful for you to use as a future suggestion for others.
I’m using themify builder and like many other visual composition software it breaks out of the usual WordPress publishing methodology.
My trick is to add a text box (builder component) at the bottom of the post and add all the media attachments used in the this post. I then add a <noscript> at the beginning of these attachments and a </noscript> at the end in the tinymce text view option. This in turn attaches all the images to the post but of course doesn’t display or load them so they have no effect on page load, the DOM, page rendering and probably more importantly load balancing.
You can see how I did this here if you want to take a look:
https://dcl.reeskenyondesign.co.uk/wp-admin/post.php?post=544&action=edit&classic-editor
Thanks,
Rees.