Well, after reading all the previous posts, I think I won't even try to use my certificate.
Chalk this one up to experience. Dockers and Kohl's got a boost in sales. We got a fairly good discount on the Dockers' purchases, but not sure we would have bought $100 worth except to qualify for this promotion.
Lesson learned. Think I'll pass on any such future promotions like this unless I can check out the company handling the promotion.