The thing is, this "spoiler" only confirms what was already obvious. It doesn't take a genius to look at this series and realize it's a comedy rather than a tragedy. Like, no shit the he comes out on top, it's a fucking cooking manga in a fantasy setting. The real meat of the segment was that it implies to the reader that the mc won't be present in the fantasy world come the end of the story. I say this because the king speaks of his dear friend as if he is no longed present. Think about it, if the mc was still around, why would the king say "my dear friend" rather than the MC's name? This leaves two options: Either mc dies or gets sent back to earth. As previously stated, this is A FUCKING COOKING MANGA. This is very clearly NOT the type of story to kill off the mc. Because of that, the story must conclude with the mc being returned home.
This is a Shōnen, not a Seinen, we were going to be getting a happy ending no matter what. It's literally tagged as a slice of life.
However, I am making some sweeping predictions. As such, I wouldn't bet on the long-term validity of my claims.
Shit, am I over-analyzing this?