Maahir's Gambit 2.0

What changes do you think would be enough in the original scenario so that the work of a map editor is no longer considered plagiarism?

Completely redraw and completely rewrite it. The point is that the map is a finished product (not counting subsequent "polishing").
It has some idea, balance, and the developer's vision for the gameplay on it. In general, it is his creation. And if you add a new coat and a nicer hat to the creation (or, in this case, a less nice one), the creation will not become someone else's.
Therefore, in my understanding, new means new. It's one thing to be inspired, and another thing to simply spend a couple of evenings tweaking someone else's work and releasing it.
I think it's a normal idea to edit other people's maps, but the authorship should remain with the original, and such "Creation" should be justified - for example, fixing an important bug or removing something that breaks the balance.
However, this is a very abstract situation, and I have not encountered such a thing.