That's been fixed in the newest update. I've just tried it and the pictures I've gifted are gone. Also in the new update, I gifted someone a picture I drew, and they acknowledged it was a sketch of them.
9 days ago(+1)
You lost the infinite gift, BUT if you scan your drawings into a computer with the scanner before gifting it, you can post them on Inkmorrow and make passive income in the background instead! The posted scan will keep earning even after you gift the physical, original art piece.