Okay, so from what I can see, the choice is to use a forged document to evict the people, without letting on that you are a fraud. I hope you guys have backup plans, if this fails.
"You've got a deal, Mr.?"
"Call me Ron. I'll be here, if you need me."
Standing up, you gesture to Fjord and Tomas to follow you outside, behind the tavern, where you have some privacy.
"Alright, what's this 'bout?", asks Fjord, ever to the point.
"I've found a way to gain passage to Lian City, free of charge."
They look at each other, than at you, skepticism all too clear on their faces.
"There was a man there, Ron, his name was, who had a spat with another trader. If we can evict the trader, he'll give us a free ride to Lian City, or even to the gates of hell itself if we wanted."
Fjord smiles, while Tomas pales.
"Alright, some bone-breaking. Where's this merchant?", says the rather eager Fjord.
"You can't possibly want to hurt these people? I'm not a fighter, I faint at the sight of blood...", says Tomas
"Pah, you pansy music-maker, just stand back and let me and my boys rough up this idiot trader. Where's this guy?"
"It's a woman, actually.", you say.
This gives Fjord pause, and you capitalize.
"And also, I don't want to resort to violence that quickly. I can read, and write, so I should be able to make a letter of eviction, enough to send the trades-woman away. The only problem is that her husband is a guard. If the woman asks us about its authenticity, we're not obliged to show her, but if the husband comes around, we would most likely have to show him, and the deception fails."
"So, Fjord, you and your, what, five or so men, will keep watch while I alone deal with the woman. I'll approach her when no one else is around. If you see the husband guard coming..."
"I knock him over the side of the head?"
"If you can.", and he waves your criticism aside, "But make sure to do it from behind. I don't want anyone identifying you or your men. And remember, that's only a last resort. Gather your men, I'll meet you in the market district. Tomas, you just stick back here, I'll contact you."
The two men seem okay with that, so after watching them go back inside, you troop off to the market district, where the bulk of the city's trade occurs.
Sorry if I'm taking too much liberty in devising this plan, but you guys need to give me more details to work with. The entire point of this Forum Game is to give Bay12ers a chance to make convoluted, dastardly schemes.
So yeah, please, if you have an ingenious idea in mind, suggest it.