If the PDF writer is setup properly, printing to the PDF writer will create an exact electronic copy of whatever would otherwise be printed on paper. i.e. It should be an exact copy of what Preview shows.
Try printing to the PDF writer from a word processor file containing a photo and then (using a different file name) from a graphics program. Did the PDF writer create an electronic copy that included the photo in both cases? If not, then it is an inadequate PDF writer or it didn't install correctly. (Some free software is badly crippled, but others are as good as the expensive stuff.) If it did create PDF files containing photos, try again from PAF. It should work. (Make sure that "Include photos" is selected.)
If you don't have PrimoPDF installed, download it and install it. (You can have multiple PDF writers installed on the same computer.) The address is primopdf.com
You should be able to email the PDF file to the printing company or take it there on a flash drive or CD/DVD.