Hiya DasHouse, we just tried out both of these install flows, and they have fixed the issue. Manually downloading a game on Itch built with their DLC system is kind of a nightmare, so we have offered two install solutions.
If this doesn't help, yell at me again.
Sorry for the annoyance, and thanks for giving us a shot.
https://holodexxx.itch.io/hdx-home-ep2/devlog/155890/installing-holodexxx-home-and-episodes