What do you mean by "poseurs"? That Ro could've spotted Eddington and Riker as Maquis before anyone else? How would she be able to do better than anyone else at spotting Maquis?
W. Thomas Riker deflected O'Brien by offering a cold shoulder, and he would've had to have done the same with Ro. As for Eddington, was there really any indication that he was Maquis before he defected? What would she be able to see that Sisko didn't?
By poseur, I mean they were pretending to be rebels when "the cause" was just something they were adopting to work out their own issues, like Riker's frustration with living under William Riker's shadow. Imagine that Ro is on one of the bases Eddington flees to after outing himself as a Maquis. She meets him and immediately he rubs her the wrong way: he doesn't really have an iron in the fire, he's just fighting to play the part of rebel, because it's more interesting than being an office clerk on DS9. It'd interesting to see a plot where Ro and Eddington are both pitted against Sisko, but Sisko is able to use the animosity between the two to foil some idiotic plan of Eddington's. Think of the effect the Dominion cooperating with the Cardassians had on the Maquis: they were destroyed. There could have been an episode where Ro is trying to lead some of the Maquis to the safety of Starfleet and Eddington tries to fight her, because he can't stand the idea of going back to the federation without having proven himself as some macho man on the front.