As much as people aren’t keen on the Pan=Papastiltskin theory, I do have to mention how they specifically said “fresh start” in the press release, in regards to what will happen between Rumple and his dad. “Fresh start” to me implies that Malcolm is de-aged, hence a fresh start. It’s also likely that if Pan is Malcolm, he doesn’t initially have those memories if ever. Normally when a person is de-aged, they lose their memories from past the age they revert back to.