I'm trying to complete this quest in the Groundbreaker after having completed the bounty for MacRedd peacefully (lying and using his lighter as evidence). I would really like to try and take a non-violent approach here, but I can't access the area in the back bays where the parts are without MacRedd and his people getting hostile, and there is no dialogue option to talk to him about it.

I read that if I have a save game before i could talk with Junlei before, but i have no save game before. Please add a dialog option to ask MacRedd for the radiator AFTER have complete bounty quest. PLEASE I DONT WANT TO KILL THEM ALL AFTER HAVE TAKE THE PEACEFUL WAY BEFORE. 

There is a duct you can crouch and crawl through to get them sneakily. I believe it was off to the left near the entrance? Try that. 

In having the exact same problem, and I've even tried a fix someone suggested and no such luck. I've done so much crap in between the bounty mission for him and this one that I don't even have a save to go back to. I'm literally forced to slaughter them all unless they fix it.