100% agree with OP. I can see MAYBE Sarevok after being tormented for 100 years in hell with daddy-dearest. They could have stressed that if that was the case, though. But Viconioa? Never. They just should have used a no-name cleric because they wrecked her beyond my ability to suspend disbelief.

Also, I have to do mental gymnastics with Balduran since most of that time-line has major holes - not the least of which he was believed to have become a lycanthrope. Not even a mention of that whole boat trip and how he managed to escape it.

Other lore was mangled, too. Balduran did not found the city of Baldur's Gate. He built a wall to protect the part of the city the elites didn't bother with and the gate of it was named after him. People started calling the city after that gate.

After a while, you become numb to all the plot holes, dropped balls, and obvious errors since there are just so many.