Follow the instructions in this article to attach the PDF you'd create outside of ProConnect Tax for that attachment.

Make sure you choose the following from the dropdown on the line for Link to form (defaults to main form): Form 8283 > 37 = Form 8283 - Other

https://proconnect.intuit.com/community/electronic-filing/help/how-to-attach-a-pdf-to-form-1040-for-...