I am having a similar issue. I have told PageBuilder the correct graphic I want to use but it keeps putting in the thumbnail instead. I want Facebook to pick up the larger image to make a wide image post. PageBuilder, as you can see, tells it to pick the thumbnail.
<meta content="http://www.inventright.com/images/2017/12/08/_spmedia_thumbs/osi-fb-graphic3.jpg" property="og:image" />
Any idea how to tell PageBuilder to list the full size graphic as the og:image?
Thanks!