shareFile adding attachments to every thread item?

Content

I am developing a CPM that copies a number of fields from a parent incident to a child incident. I found the "shareFile" functionality, which is great for the attachments. It's working great, except that after the attachments have been copied, the child incident shows the attachments connected to every single thread item. (See attached picture.) If I look at the attachment tab, there are just the two attachments, so it's doing the right thing, except for how it appears to be attached to every thread item.

Here's the relevant code:

$incident->FileAttachments = new RNCPHP\FileAttachmentIncidentArray();

 

for ($i=0; $i < count($parentIncident->FileAttachments); $i++) {