Because the hack is broken by design:
This blog post explores the notorious " Pokemon Messed Up Version," a ROM hack known for its extreme departures from traditional gameplay.
While "Pokémon Messed Up Version" isn't an official title, the phrase is a common way for fans to describe several distinct categories of unconventional or disturbing Pokémon media. These range from official games plagued by technical issues to fan-made horror experiences. 🕹️ Technical "Messed Up" Versions
Fans of the game enjoy the shock value and the unpredictability of the writing, viewing it as a parody of the often self-serious nature of other fan games.
Fans have created "messed up" versions that lean into psychological horror or disturbing themes.