As a fellow TTRPG designer and fan of Kafka's work, I was glad to see someone else attempting to translate his work into a gameable adventure. A few years ago, I made a little, two-page dungeon adventure based on The Trial. In doing so, I shared the doubt that you expressed here in this "lyric adventure" that the situations in Kafka's work are not immediately playable in the typical TTRPG framework.
However, I do think that it is possible (and effective) to create a more traditional adventure--complete with maps, keyed areas to explore, specific NPCs, etc.--that evokes the same atmosphere of uncertainty, want, and dark comedy that defines Kafka's work.
Anyway, this is all to say good on you for writing up this little adventure! I hope you keep at it and turn this into a more traditional, playable adventure with NPCs, maps, keyed locations, etc. that embodies Kafka's themes while ensuring the players have agency and their characters have goals that are recognizable to exploration/investigative games.