Maidhc O Casain
Na Bith Mo Riocht Tá!
A quick glance through the journals and ledgers shows them to be records of dealings and agreements between Avret Kinkarian (Captain of the Brine Demon) and various people in Bloodcove and Sargava. It'll take more in depth study - likely with Jask's help - to be sure, but it looks like this might be the proof the cleric was looking for.