I answered your post wrong sorry I thought you bought the item for a resell sorry. Now that I am on track let me see if I can add a better more to the topic comment.
My fist question is what did you pay for the item. My best guess was you paid 69 not 189 is this correct?
Being in this business if it were my mistake and you did pay the lesser price I would have offered you the item for % discount, subtract the amount you have already paid, and ship the item to you on my dime. More or less I would just do the deal at a break even cost. This way your happy and I as the seller didn't lose either.
I would not ship the more expensive item for the lesser cost that will not be an option for me.
I would expect that this is what the company tried to do with the 33% discount and one I feel is fair and should be either accepted or rejected with them getting the product back and you getting a full refund. Trying to get them to cough up a bigger loss as well as the shipping pickup and reship the item is to me not a option I would ever do and or expect.