Hello Steph,
It's great to hear that you're willing to learn how to prepare a CAD pattern for a print shop. PDF is a common file format preferred by many printers, and it's understandable that your Grafis system doesn't support it. But don't worry, there are still ways to achieve what you're looking for.
One option is to export your CAD pattern in a format that is compatible with a PDF writer. You mentioned that you usually print tiled PDFs, so perhaps you could try adjusting the settings to print a full-scale pattern instead. Another option is to convert your file to PDF using an online conversion tool. These tools are easy to use and often free.
Overall, it's great that you're willing to go the extra mile to meet your client's request. Keep up the positive attitude and willingness to learn, and you'll find a solution that works for you. Good luck!