Nah, everything's fine. There are two ways to get the A.D. ... either pay Barlone' a ridiculous sum of money for it (90,000 GP or something like that), or kill him and get it.
Killing him is no mean feat; congrats!
Oh, and BTW, if you remember him from Wizardry 7, he is no angel...he pretty much "raped" his homeland, sold his home world out to the invaders, then double-crossed the T-Rang and snagged a ship of theirs and that's how the Ratts got to Dominus. Now they're doing the same thing to the poor little Trynnie. You did Dominus a service!
-Sazerac