Ah, you're right. I forgot echo appends a newline by default.

When the -n flag is added to the echo command (as suggested by ata) the hash matches.

So, unless orthonormal has exploited a security vulnerability on the Less Wrong server, orthonormal has expended a costly number of computing cycles to defeat the purpose of the hash function, I misunderstand the cryptographic guarantees provided by the hash function, or something equally unlikely, orthonormal really did write the following back on 25 July:

End of 32 only listed 3 options for Zabini. The fourth creates a 3-way tie. Zabini shoots himself as traitor.