Talk to Torbjorn about Scouts-Many-Marshes

Walkthrough
If the Dragonborn speaks with Scouts-Many-Marshes at the Argonian Assemblage in Windhelm, he will mention that Torbjorn is underpaying the Argonians for their work. The Dragonborn can then offer to speak with Torbjorn about the situation. Torbjorn will either be at Candlehearth Hall or walking around the city.

If the Dragonborn's speech skill is sufficiently high, a simple talking-to will suffice. Otherwise, intimidation might be necessary. Sprich mit Torbjorn über Erkundet-Viele-Sümpfe