I wouldn't either. One wrong step from you and it's ruined. He's offered the olive branch, and he obviously trusts you. Continue the "do-nothing" approach, I reckon. Finish his books and expect nothing in return. You'll get your view.
Agree, being civil saves dollars in the long run. Personally I find his attitude a bit tosser like considering he is taking this to court. But grit your teeth and let him lose a few more coins on lawyers.