Wow, I could have written this! First, your concern is a warranted one. As other sellers will tell you, there is NO SELLER PROTECTION on eBay. EBay is for the buyers. Yes, it is true. I know. I just learned this firsthand.
I just had this issue happen to me. I'm mostly a buyer, 99.9% of the time, I shop on eBay. Then every few years or so, I sell some things I no longer need or have room for. This time I sold an electronic Monopoly game. It worked for the few years i had it. It worked when I listed it for sale, and again it worked when I sent it to the buyer. She had it for three nights. She said on the first night the sound worked. Everything was fine, then on the 2nd night there was no sound. On the next day, she went out and bought new alkaline batteries, but still no sound. She began a return request via eBay. Though, eBay suggests buyers and sellers work things out and contact them only if needed, she didn't contact me. I thought I had no choice. I'm a buyer, usually. I accepted the return. eBay said once I get the return, check it and make sure everything is correct and fine BEFORE issuing a refund. Of course, I received the return incomplete because the buyer didn't send the hard copy operating instructions. to protect myself, I phone ebay and spoke to four different persons, including two in Mediation and a Return Specialist who advised me that I could choose to "wait for the return of instructions and then issue a refund" which I chose to do. But what eBay told me and what they actually did were two different things. They issued a FULL REFUND to the buyer and I am still waiting for return of the instructions, as well as seeing pigs fly in the sky. I appealed the case while on the phone with a mediation specialist. The Appeal specialist (and I use the term loosely because there is no actual opportunity to appeal anything. eBay made the decision and it stands.) at first wouldn't even speak with me. He relayed everything through the Mediation Specialist. Finally he came on the line. I pointed out the eBay's Condition of returned items, which clearly said "the buyer must return all of the items sent in a return that was sent to them including manuals, etc. in the same condition as sent out. I pointed out that I had to pay to get the game professionally cleaned because of the smoke. eBay said the Refund was issued and they would not help me get back the instructions. "What do you want?," he asked. I said I want the instructions back and what I had to pay to get the game cleaned, which was a token amount. He said, we'll refund the token amount to me within 48 hours. Guess what? No refund for that to me. Well, needless to say, like you I am totally discouraged with selling on eBay. Shopping may be easy, most of the time, but selling isn't.
As to your case, your issue has probably come and gone by now. For future reference, eBay does have a time period in which the buyer can do a return, which is 30 days. You said a month passed. Not that eBay will help you, but if it was past 30 days, I would appeal it. As to your questions, I hope nothing like that happens. The problem eBay sellers have is this: the customer is always right. The customer is always right. More so, as more experienced sellers will tell you, eBay has no way in knowing what you sent her and what she sent you back. You need proof. Yes, an unbiased witness like the mail carrier wouldn't hurt. Photos with the item with the carrier wouldn't hurt either. Would it help? Good question, I don't know. I've heard a few (very few) cases where the seller did win because they had proof to show eBay. I had a receipt for professionally cleaning the returned game, but I don't have the refund from eBay, so that is not evidence.
In my case, and yours, on the return page, eBay says to "click here" if there is a problem with your return in order to have eBay step in and "help" you. I telephoned eBay but they didn't help me. Four different persons there all gave me the same story contrary to what was actually going to happen. I tried to protect myself. It didn't work.
I really wish you the best with the Tiffany earrings. I do have a question, how do you know they were authentic Tiffany earrings you bought? Do you have any kind of store receipt that says that? That might help. If not, and you do lose your case, the best I can say is accept it and move on. Complain to eBay corporate office about the need for seller protection. Complain to everyone in authority you can. Just don't let it be the center of your universe. Do what you can to help others, what feels right to you, then move on. Life is too short to take eBay seriously. Face it, it's just a big garage sale where most buyers want to get the most they can from sellers without necessarily paying for it. Personally, I would never, ever sell anything really valuable on eBay. And our experiences are the reason why.
