You can visibly see in your example that the margins are different.
Print Setup is a script step that you can use to control some settings:
Under Layouts > Layout Setup > Printing tab, have you configured static margin settings there?
I am experiencing the identical problem. I developed my print layout in FMPA and it is currently in v14 with all updates. My client accesses it, as I do, from my server also latest version of 14. The only difference is that she is using FMP not FMPA, and she is in a different location, presumably with different printer configurations in her print dialog. We are both on Macs She prints to PDF using the same scripted button with Page Setup and Preview (Pause), Continue to Print scripted button that I do. She ends up with a whited out strip down the left side throughout the 14 pages. This has been happening since last year. She prints this layout once a year, and since when I do it, there is no problem, and I cannot replicate her problem, I have just sent her the PDF my system generates, but this is clearly not a long term solution.
While in pause and preview, I have tried to print to pdf, save to pdf, all the different ways available, with no ability to replicate what she comes up with. Yet she sent my the file and it definitely has the missing area on the left.
Please let me know if any of you have similar problems or any possible avenues to explore a solution.
PS. I added the PDFs. If you look down the left side you can see letters of the names cut off on the Photo Pages 2.10.2016.pdf which is my client's and then not cut off on mine Current Photo Pages.pdf.