From my personal experience setting up jobs like this to print: the safest way to do this is to provide as merged/compiled document as possible. It varies from printer to printer but I prefer PDFs. If the document doesn't have tabs I'd ideally want one PDF to print from. If I receive multiple files, I have to convert them all to PDF and import them into indesign and merge everything to one print file for the printer. If you don't merge everything together beforehand, someone else has to do it, and you usually pay for that setup time. If you provide word documents, they tend to open differently on different versions of word, so there's risk of something going missing. Saving them as PDFs helps ensure your entire document gets through the print process as you designed it.

Hope this helps for next time.