Sooo... anyone asking themselves if the MoM can really return at any moment without Luxu's and the Foretellers help?
I think it has been pretty obvious from the get go that MoM can easily traverse worldlines or wherever he went. I've been saying this since day one but he is totally a god-like being. He has no issues going between worlds but he wants his apprentices to really believe he's gone and that they have to bring him back.
Also, does anyone wonder what that exchange between Yozora and Sora was about? Yozora saying Sora sees him as Yozora and Sora using Sora's name? But the Yozora we see is the real deal, since we see that same figure in the car.
We don't know if Yozora in the car IS the real deal, though. It's clear that they want us to not see what he really looks like. After all, Nameless Star says that the person she pines for has been "changed beyond recognition" and that his heart has been replaced with another.
It is implied that Yozora seems to be familiar with our Sora, but also another Sora (potentially Nameless Star).