EastScape Wikibuilt from the game itself

The Audit

The Auditor has a question for Dex the Dealer. Carry the ledger to the casino, hear Dex out, bring it back signed.

“Take this ledger to Dex the Dealer. Have him sign it. Bring it back. Watch his face when he does.”

He's at the tables, top of the floor. Don't let him keep the pen.

Steps
  1. You are handed the auditor's ledger. Talk to Dex the Dealer
  2. Bring 1 the auditor's ledger to The Auditor
Reward7,000 tickets, 4,000 Thieving xp