The Demon Layer isn't locked behind donations, it's friendship with the girl in the church and a minimum stat score. The Holy Headpat isn't actually tied to friendship with her, you just have to talk to her about combat.
It's known, and there'll probably be a hotfix soon. There's an unofficial fix in the discord server (#bug-reports), but it doesn't work for android afaik.
Anyways, a lot of people reported it, it's just all in the discord server instead of here.
