SPOILER Book Problem When Near Pnj

I was near the "bad" man of Iron Heart II and opened the book for see if it's a choice quest, it was, but when I opened the book at the same time the NPC activate is script when I was not looking at him, of it hitbox problem I didn't chose the choice I wanted... So it will be good to prevent the future adventurer who pass after me, and can I know if I can trade what I get from the mission with the prize from the other choice ? This quest will be ever the one I hate the more cause of this... Thanks for reading me.

Edit : And I didn't win one of the "greaves" we should win in one of the choice...

Edit 2 : And now the only prize I get dissapeared from my inventory ! What the heck is happening to me !

 

What's a Pnj?

 

NPC sorry I writed that in french x)