Hello Guys,
So no one answered me, but I did find the solution (and in case someone needs in the future).
So apparently this extension uses chromium print to pdf to create the pdfs.
After searching for a bit, I learned that this feature doesn't detect page-breaks under certain css rules.
The problem I was having happened because I had a container with display: inline-block.
This came from a container that had it's width set to 11 col (which uses a style that has display: inline-block). When I set that container to fill width, the page-break just worked.
So guys, if you plan on using page breaks inside something, don't set it or the parent divs to have 11 cols.
Best regards,
Jose Torrao