As for the letter, it looks to me like Allison took a real letter from Aram and tacked on that last sentence. Looking at the chain as a whole, it simply doesn't fit. It also doesn't fit Aram's style, his writing style, his opinion of Allison, or the sequence of events. I mean, why would Aram offer to bribe Allison with the Book, then when Allison offers to bribe Aram with the Sceptre he turns around and blows the whistle on Allison? That would be dumb. Also, Allison's letters make no mention of Aram's attempt at bribery, like "how about instead we do this?" And that letter is just so disconnected.... I'm 99.9% sure it's a partial forgery.
Brance is pretty sure it's forged, for all those reasons I listed above. He knows both of the involved partied *very* well. (Aram married Brance's sister back in Perdan on EC, and he's known Allison from back in the first days of Dwilight.) He will probably let others deal with this. He's tired of dealing with Allison's crap.