[Rusty0604]

I don’t get it.

[Steve_Seattle]

"I don't get it."

It seems possible - even likely - that the manifesto mentioned a specific teacher or teachers as well as the school's general stance on LGBTQ+ issues. The names of the teachers could be redacted, but probably not the school's policies on those issues. To redact that information would subvert the purpose of releasing the manifesto at all, since the primary purpose of releasing the manifesto would be to understand the mindset of the shooter.

The school probably fears that releasing the manifesto might trigger a copycat shooter. In other words, they understand that the trans community is unstable and dangerous.

[Tom Tetroxide]

They have something to hide that would prove very embarrassing to the school.