Send a letter to Hickory Chair. If the chair doesn't hold the down, how can they let it be sold anywhere? Other than that, have a nylon bag made to hold the down, put the down in the bag, and put it back in the cushions. If you do this, let us know how much chicken feathers and trash you find. Down is fluffly and very light. Feathers look like feathers and are not fluffly.
Was it made in China?

hold on to the nylon bag idea, I dont think Hickory chair is making any sofas in China, first unzip the back of the cushion to remove the insides. Then inspect the ticking, looking for any broken seams or punctures. Manufacturers use a special down-proof ticking to keep the feathers where they belong. Feathers have a small quill that will work their way through normal fabrics, and the real down doesnt have this quill so the down will always stay inside. If you see any feathers poking through the ticking then Hickory Chair's cushion supplier didnt use a good quality down proof ticking. Very few upholstery manufactures manufacture the cushions, this is done by a speciality cushion converters. Hickory Chair is a larger manufacture and has several cushion suppliers. I havent seen to many outlet centers that didnt offer some kind of warrenty, how long ago did you purchase the sofa? Most re-upholstery shops can make repairs or can get the down proof ticking and make a new envelope for you.

That's what I was going to say.