Look, you're not wrong but WoTC made every possible terrible decision in establishing that canon adventure.
As far as I know the only "canon" part is the name (Abdel Adrian), the gender (male) and that he also ended up as a fighter.
The books are *not* canon since other stuff directly disproves them (Minsc has nothing in common with his book version, for example).
Also, if memory serves, Abdel Adrian was one of the Predefined Characters in the original BG1 or possibly the TotSC expansion. He was not an invention of the book.
The fact that he is in Baldurs Gate and that Bhaal returns is not so bad (blame the Second Sundering which apparently lifted the seal on the essence).
Using that name, however, was a terrible decision and they should have stayed more vague during the adventure.
Kudos for remembering that Viekang should have survived ToB though, I was positively surprised that he was the one who attacked.
