Hey there Abacab. I actually felt the same way after killing him and the scribe 3 times or so. Was about to leave(even made a bug posting) and the last scribe we killed before leaving dropped the tome finally to my surprise and glee.
[You must be logged in to view images. Log in or Register.] So that gave me hope, and the subsequent One Eyed Gnoll dropped his eye finally as well. So roughly was 1/4 or 1/5ish on them both~so roughly 20% drop rate with that low data.
This was over a month ago now though, so its possible something was changed; more likely you just had some phenomenal bad luck. Its a great weapon, stick it out!
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