If you are talking about the river dividing us, that actually is a pretty wonderful advantage assuming we are not outlined in it by the moonlight or having to maneuver through it in combat or with haste; after all, who attacks from water? Least likely route of approach and a false sense of security, because anyone who can maneuver through it can leverage it. From what it sounds like, with the amount of smoke present obscuring ambient star and moonlight, if we went further down west, off the map, crossed the river and came around in a hook and formed an "L", they would need to maneuver either down the road or across the water - the former I can only imagine they would favor.
In that case, the raven can also be our eyes from above to see if there's more marauding bands further down the road before we attempt to strike, that way if they do flee, we already know what the consequences are. If done correctly as a close ambush, with someone like Orchid on the furthest part of the "L" to the east, he should be able to mostly entrap them. However, reasonably, Brannor as a character could get as far as outflanking the enemy, maneuvering through the water out of sight and attacking them from the side and behind. Trying to use tactics beyond that are safely beyond his expertise, but between everyone present I think the notion of an ambush and checking to see what is further down the road is reasonable.
As for it being a trap? It is already clear our paladin is present simply because he would rather not see these people he's fought beside needlessly perish. To hell with the mill and "capturing" a person. Parum and Kyra are the only two convincing him it is of some importance.