Seller refuses to buy Shipping Label, now refuses shipping cost.

[bvco5326]

Hello, I am new to the eBay Community, and really need some help. I recently had the bright idea to buy some used headphones on the eBay and turns out to be really bad.  Seller said it was like new with no sight of use but fingerprints, which turns out to be lies and it was full of animal hairs. I opened a case and went on as usual, and unexpectedly seller refused to cover ship item. I asked the seller to cover and they only replied " Open a case" which is redundant since I did already, after that seller no longer response to my questions. I tried so hard to contact eBay help center, but there is no way to call them at this point, the option is not there to call them or have them call me.  On the help center when I clicked on that item it only shows the link to open case. Another couple days passed, eBay alerted  me to ship the item back, so I did and it comes up to $28 usd, and its $2 cheaper than the original shipping. I sent a message to seller and here's their response, "I stated open a return request. We would provide a label that would cost around 8 dollars to us. Im not reimbursing the $28." It's just a lie after other, I opened the case, they refused to buy the shipping label at the first place, and didn't reply when asked, I couldn't have closed and reopened. The seller shipped it in a big box originally and as eBay guidelines stated I had to send back like it came. And there is no way that it could cost $8 to ship it back from Ontario, Canada to California, USA as the number eBay Shipping Calculator came up, my shipping cost and their shipping cost are all very close.  After reading their message, I tried my luck in help center, and the Call options actually came back after shipping. After telling the operator  about my situation, she told me that I should have called when seller first refused shipping, which I had to explain again and again that there is no such option before I ship the item as it would only give link to open case.  I told her the seller is trying just get back at me for returning and shipping is not possible to be $8,  and she said that the only thing she could do is to send seller a message about my complain, at which point they can agree to pay the full amount or pay the amount of $8 they made up. Really need advices on this case, any information on the topic would be greatly appreciated.

[bvco5326]

After double checking everything, I kind of realized what he is trying to do. First he refused to pay, so I have to ship myself. After I shipped, he played dumb and made up the $8 so he would be able to refund that much. Here is the cost by eBay, I guessed the sizes but it should be accurate since cost only  goes up greatly when increase in weight not size. So he clearly lied and hopes that I don't find out. I'm not sure what is going to happen, but hopefully eBay would do the right thing. Take cautions when sellers refuse return shipping and reply weird answers to your questions.

Screenshot (10).gif ‏88 KB