The Inquisition cannot risk sending its forces over the border into Tevinter to chase up the remains of the Venatori, not without being accused of an attempted invasion.
Dorian, however, is still a citizen of Tevinter, albeit a mildly disgraced and definitely-- as well as defiantly-- scandalously deviant one. Because of this, he can do what the fuck he likes. He has several arguments with Bull over this, during one of which they actually break a bed (not, as Varric insists on putting it, "another bed").
This is why he ends up with the Chargers hanging about in the area for 'backup'. Not their boss, who will be staying with the Inquisitor if he knows what is good for him. Dorian himself has the job of making contact with the Vashoth mercenary, Gize, who Inquisition spies have previously been in touch with. All he really knows is that she runs a mercenary band, knows where some of the local Venatori hideouts are and has some interest in helping Dorian root them out, especially if he's willing to pay her and her men a fair rate for same. That it's not actually his money is a mere technicality.
The time he's spent in the South ought to have taught him better, but he's still surprised to see his contact leaning against a wall, reading a battered copy of Corti's Summerlight. She spots him looking at the book, raises an eyebrow. Oops. "Always thought that one rather overrated, to be honest." he says, by way of greeting.
Gize looks him over. "Fifty-seven."
"You're the fifty-seventh to tell me this is overrated. Would you like to also tell me I should read Deep Waters instead? You'd get to be forty-nine."
Oh, come on. "Deep Waters is a classic."
Gize grins, showing her teeth. "It's not bad. You all say that because you think it's naughty, though. Read some Salvetti sometime." She gives him another look. "Broken Ocean, maybe."
Dorian feels his face heat, because his contact just pretty much asked him if he likes men via literary reference. It's easier to be comfortable about these things when he's in a tavern in Skyhold than when he's back in Tevinter and in Tevene, it's hard to talk about these things without using words that are basically insults. "Shall we talk business?"
"Sure." Gize shrugs. It seems to take a long time. She has a lot of shoulder, granted. "This is my patch. Good people around here. Not mages, not rich. Good people, all the same. Venatori are fucking it all up. You help us fix this, I don't care what your tastes in literature are." She pauses. "But just out of curiosity, the rumor about you and the big guy, runs a merc company called the 'Chargers'?"
Maker's breath, how far have those rumors got? "Broadly true, although I hate to think what charming little details the rumor-mongers have added along the way."
"In one version it's you, him, and the company." Gize tells him with a grin. "I'll spare you the details. Unless you call my book 'overrated' again."
"Sounds like a deal to me." Dorian says, and holds out a hand to shake on it.