Voice memos- How to do a one-way sync from iphone to itunes?

I would like to sync newer voice memos from my iphone to itunes.

The "voice memos" tab in the "on my device" section of itunes contains approximately 50 existing voice memos*. My iphone has ~90 voice memos in total. Around 40 of them are new voice memos that I want to sync from itunes to iphone.

How can I do this without deleting or overwriting anything from my phone; and without transferring data from itunes to iphone (this would delete new data)?

I DO NOT want to click "Sync Music" (and check the box that says "include voice memos) because a pop-up occurs and says "Are you sure you want to remove existing music, movies, tv shows, and books from this iPhone and sync with this iTunes library? Music, movies, tv shows, and boos synced to [my phone's name] from other iTunes libraries will be removed and items will be synced from this iTunes library." I do not want to remove anything from my iphone.

(I obviously was able to put voice memos from my iphone onto itunes once before, but I can't remember how I did it now, and that was because it was the first time and prior to that, there was nothing in the "voice memos" tab so I didn't have to worry about accidental deletion/overwriting.)

*Note: Not sure if this is relevant or not, but I previously removed the m4a files from the voice memos folder on the computer (User\[username\music\itunes\itunes media\voice memos) to another folder in my documents to a) prevent data being deleted/overwritten b) put those m4a files into folders that I want to permanently store them.