When I placed the 1st order I let them know my situation. Didn't hear anything beyond the initial "Your package has been shipped"(which means a label was created). I watched the UPS status. The day the order should have arrived was when I contacted DDF so they wouldn't ship it as I was moving in a couple of days, which they knew from my initial message. It just got worse from there.It seems to me that while they are fully at fault for sending you the wrong suit originally, they didn't actually do anything wrong afterwards. They did refund your original purchase. It was kind of a jerk move to not honor the original price, but their replacement cost had obviously gone up and it seems to me that it was their way of telling you that they did not value you as a future customer enough to eat the difference. It seems from your post that you were a, shall we say, high effort customer.
Meanwhile, the price on that suit was upped to $403 for my purchase, and is now lowered again! Hard to say if this was on purpose or they just don't know what they are doing with eBay.