Because none of us has left the loot room with boss yet, nobody had gotten their buffs, we hadnt walked past, mobs were in the way of looting it on the way in.
I literally always check for the tomes in their spawn points on the way out.
Cut the BS you ninjad and you ninjad without remorse you deserve exactly what comes of this.
If your response to me asking "you don't care that you ninjad?" isnt something like " I AM NOT A NINJA I NINJAD NOTHING" then it is very obviously an admission of guilt