There is an option in ndOffice's Outlook integration to send a link and attachment at the same time (the "Attach File" feature): https://support.netdocuments.com/hc/en-us/articles/205220000-ndOffice#email
If I may ask a question. What is your use case for sending both an attachment and a link? The Email Link feature (and the link you can send via ndOffice) can only be accessed by other NetDocuments users who already have rights to the document, whereas attachments are often used to send information to non users. I'm just wondering why you want to include both.