Allow duplicate filenames if they are in separate SharePoint list items

I have had several instances of workflow failures due to duplicate filenames in a SharePoint list. I use SharePoint lists frequently to store NAC workflow data, and many of those lists include attachments added from NAC. And, often, the attachments are documents that have been uploaded by the user using the File upload function on the NAC form. So I have no control over the names those files are given.

Let's say User 1 completes the form and attaches a file called "Document.pdf." User 1's data gets written to the SharePoint list, and the file is also attached to the list item. Then User 2 completes the form, and he also attaches a file called "Document.pdf." This second instance of the workflow will fail when it tries to attach the document to the SharePoint list item, because of the duplicate filename - even though the attachment is in a separate item in the list.

I am aware of the Overwrite attachments option in NAC, but I don't want to use that - most of the time I need both documents to remain in place. In the above example, I need User 1's "Document.pdf" to remain attached to her list item, and I also need User 2's "Document.pdf" to remain attached to his list item.

What would be quite helpful is if NAC would allow duplicate filenames as long as they are in separate items in the list. A while back, an NAC community member gave me a suggestion for how to avoid the problem, but it's a roundabout solution requiring a lot of extra work. Users are inevitably going to use filenames that are generic enough that other users will use them too, and I can't have instances failing because of the duplicate filename problem.