Sorry guys, I should clarify, my question is not whether the Archivist can find a divine version of Fireball. You can essentially substitute that for any spell you want.
The question is, what is the Archivist's spell list? If an Archivist finds a non-Cleric divine scroll that he hasn't yet scribed into his prayerbook, can he cast it from the scroll without relying on UMD or similar?