I managed to get that scene on my SW fortunately, but only because I got spoiled about it beforehand.
It doesn't matter if you take Quinn with you on all Corellia quests or not, but you must NOT have Quinn with you when you talk to Vowrawn back at his safe house on Corellia.
Just switching to another companion right before you talk to Vowrawn does the trick : I summoned Jaesa at this point, spoke to Vowrawn and he commended Quinn for saving his life, not Pierce.
To be on the safe side, you could just summon Pierce before the conversation though. My character's affection with Pierce was never high so I have no idea if it has any effect on how the scene plays.
It makes sense if you think about it, as the "mysterious assassin" attacks Vowrawn on your ship, so if Quinn was with you on Corellia there is no way he could have been on the ship and save Vowrawn's life.
But, considering I had Quinn with me all the time on Corellia and dismissed him only before triggering the conversation with Vowrawn, he technically wasn't on the ship when the attack occured
It can help with the relationship as you said, but to me, it just seemed that Bioware wanted to railroad me (again...) into hating my favorite companion with that "incident", so I mostly chose to ignore that part of the story.
I was just relieved we got the option to forgive him and that scene on Corellia was just an added bonus.