All I can say is wow!
Kathy, the manager at our local OfficeMax just called and was super sweet! She was very interested in our situation - the twins thing. I mentioned to the other person (Diane) about how it was difficult for me to return the chair earlier due to the complications of pregnancy with the twins. That was true. Anyway, Kathy said she was really excited for us. She sounded sincere. She explained that she's been "out of it" due to a botched oral surgery and apologized for our difficulties we encountered in returning the chair.
Anyway, she offered us a gift card for a little more than the value of the chair. It's not a cash refund, but it's something and Dave and I are quite pleased.
Lesson reaffirmed: if you're a dissatisfied customer, take it to the top!