- Talk to Flo until you exhaust your dialogue options and she asks to meet the Rangers in the cemetery.
- Meet her in the cemetery and accept the job.
- Talk to Swifty and ask him repeatedly about slavery (the slavery dialog option is not available until you are given the quest from Veronica to investigate the "agents" in Schwag's). He will ask the Rangers to talk to him in his office.
- Meet Swifty at his office (a couch and a box next to the entrance to the sewers, a block south from Hotel California).
- Ask him about slavery, only to fend off an ambush of four slavers. Head into the sewer. Kill Swifty and four more slavers.
- If Swifty is not in his office, the Rangers can simply enter the sewers and try to open the cages with the slaves.
- Loot Swifty's Orderbook from the military crate near the entrance (in the enclosure with the three green crates).
- Deliver it to Heidi and inform Veronica.
- To truly fix the problem, the Rangers have to hack or brute force the door to get into Duke Schwag's office and question him about slavery, which will cause him and his guards to attack the rangers.
- Loot the safe to find Duke Schwag's Ledger.
- Talk to Flo about her taking the diner operation over, since Schwag is dead.
Experience, and nothing but.