Was für Notationsexperten?

As a player in this real quanta sequence we should not forget that we are heading towards a beautiful tonal conclusion in our tone g-moll.
However, in the case of the constricted chord there is nothing to suggest, even the following chord follows the logic of the quint case sequence. That’s why the closest notation would be Ges-B-Des-Fes. Fes, because it is the Septime that dissolves in the next chord into the Es.
In the penultimate chord of the piece makes the Fis sense, it is the term of the Dominante D major.
Of course, the composer is right that the listener wishes the Grundton G all the time, and the fis expresses this longing, but it is not usual to simply write a chord with “enharmonic mash” in any place as you say correctly.