Back out about 12-20 feet or so and each of you cast or pitch parallel to each other towards the reeds, anywhere between parallel and 60 degrees or so to the reeds. If you picture a grid of the water you are covering, it isn't much different than a single angler casting along the reed line, you are just sharing the water. Sure each cast will spend less time in the zone, but that's not going to be a significant issue. In situations like this, I find fish are in clusters, and you can do a long stretch and then circle back latter.