You're in the right, so don't give in. It was a very poor customer service that got you into this mess and you are completely entitled not to pay a cent for a product you were practically forced to acquire.
Life isn't fair?! Great answer from someone who sounds really incompetent to me. I'm not aware of how things work in the US but don't you have complaints books and consumer rights services? Couldn't someone working in one of those areas advise you on how to proceed to exert your rights in the most effective and painless way for every part involved?
You can always talk to your superiors and make them aware of the situation, like someone on this board suggested. I think it's a wise advice and would probably be a sure way of settling the matter (or at least a starting point).
Anyway, good luck!
