I bought, and currently own it on Itch.io. I downloaded the Android APK from here. I probably downloaded it first around time of purchase 2023-09-07 10:20:27 but I only got around to playing it now, after a change of tablets.
Oh, you must mean you can't download the Walkthrough. It cost 5 USD extra back when the game cost 25 USD, currently the game is in a 20% discount so what you currently see as 25 USD price for game + walkhrough was 30 USD back when you bought the game, you didn't buy the walkthrough back then (and maybe it wasn't even available yet at the time)