Hi! My apologies for not replying earlier.
The Wits roll you're talking about isn't a task roll in the sense of "can I ascend this person," but is rather assessing the character's ability to understand the community they're in. Failure is best narrated in the context of what the player says the character is doing ... or to put it better, don't have any dice rolled until the character's location, actions, and attempted interactions are being clearly imagined by the player(s) and GM.
If the actions are relatively passive, like, "I hang out by the seashore and keep an eye on how people interact," then the immediate consequences of failure are minor. Maybe nothing. At most, someone takes note of the stranger hanging around, which is happening anyway. But the real consequence of the failed roll is that the character cannot understand the locals well enough to grasp where "the kind of person I'm looking for" might be - and that failure is a closed door, socially speaking, for that character. Sometimes it's hard to find the right "in" when you're in a new place, and the Iron Folk can be mighty obstructive that way.
If the actions are more focused and interactive, then the consequences of failure can be expanded to include immediate repercussions. These are far too specific to the moment of play to generalize about, but on the other hand, they're also pretty easy if you're in that moment yourself.
Let me know if that helps or makes sense anyway.