I agree with sparklemotion totally - I would send them a quick email saying you had to pay that fee also. If they do all this re prepaid labels, they don't want you to be out of pocket at all, thats all part of the (usually great) customer service. You're not doing anything wrong by telling them (I think anyway).
maybe wait a week and then try a new order? 4th time lucky? I've gotta feeling this one will be the keeper
(ha hope so!)