If I delete a voice memo from the Music app, will it also be deleted from the Voice Memo app?
I have tried it on iOS 11 with a new VoiceMemo. Here is what have I done:

I have created a new voice memo, then I have synced the phone to the computer (running latest iTunes). The voice memo showed up in both my music collection in iTunes (even separate playlist) and within the songs on the phone. At least according to iTunes. But then I have tried to search for voice memos in the Music app, but it did not show up. Was this done with some old software?

Anyhow deleting the voice memo on the computer - never mind what it says - will leave it on the phone. But of course, I suggest to back up.