Images Missing on PDF Catalog Page

I have setup the PDF catalog plugin and all the functions are working for, but there is strange issue where some of the products images are missing on PDF but they are showing on website product category page,

I have checked in the admin as well images are assigned to the products but still they are not showing up on PDF pages.

Can you please check this issue?\

Specifically you can see this page where the images are missing: https://expofair-berlin.de/produkt-kategorie/katalog-uebersicht/messe-und-eventzubehoer/garderoben/?pdf-catalog=1745

Thanks!

The page I need help with: [log in to see the link]