Just now, Bellona said:Interesting! I didn't know that. (Not that it made any difference in my corrected post above.)
Opposing a check usually works as the acting character rolling their positive dice against the negative dice of the opposition. Disoriented only applies to your checks, and the rules say nothing about applying Boost or Setback from the opposition's talents or conditions.
The confusion comes from having Ventress roll the negative dice.