Is there a way to import an audio file (of either format) into Music Memos on iOS?

I want to try to utilize the “automatic” drums of the app on some older guitar recordings. From what I can tell, the drum function listens to a memo and tries to play along, so wouldn’t it be neat if we could hand it a recording from another source and tell it “Here, put drums on this”?

I’ve been looking through the iPhone file structure in PhoneView, but I fear I lack the deeper understanding. Otherwise, copying a recording with the right format into where Music memos stores recordings, I imagine one could convince the app that this is a legit memo file. You know?