Yes. This was certainly padding or the author stalling for time while they frantically outline or rework the upcoming arcs.
It could get cut and not impact the story at all, because on the large, it provides nothing to the plot or character development.
And I don't mean the demon king appearing, I mean literally everything else in the episode.
Cliff and Elinalise getting together was at max, five minutes of content. It's 10 minutes. The tell is that there's zero issues or crisis when they get together even though there should be. Much of the rest is Slyphie "awawawawa"-ing over misunderstanding Rudy or going back to cold.
The lead-up to the fight is a full 7 minutes of stalling.