Trying to avoid making a seller overpay for return shipping

Hi there, I am trying to avoid making a seller overpay for return shipping, while also trying to avoid being on the hook for it myself. I don’t really have a good handle on Amazon policies, so I’m hoping for some help.

The situation is this: I ordered a ring from a seller who both sells and ships their own products. On their listings, it says “Free Returns” and the dropdown links to this page describing the conditions of the free returns. The ring arrived and although it resembles the listing pictures, it’s really janky looking and is pretty clearly a bait-and-switch; the seller pulled stock photos from a well-known website, and then delivered a much lower quality item. which looks quite poor.

I’ve opted to return the item, but I was surprised when the seller sent a return label that was NOT prepaid. I contacted Amazon about this and they indicated that I should pay the shipping, and then contact the seller to refund that expense separately. When I looked into shipping costs, the best I’m really finding (with tracking and insurance) is $70, which is nearly half the cost of the ring. I don’t really want the seller to be on-the-hook for that type of shipping cost, because it just doesn’t feel right. At the same time, I don’t think I should be responsible for the cost, as the product is materially not as pictured.

I contacted Amazon again, and asked about what to do. They advised the same as before: pay for the shipping, then contact the seller for a refund. When I pressed them, the support rep indicated that if there’s an issue with the seller (presumably a refusal to reimburse return shipping?) then apparently Amazon will open what’s called an “A to Z claim”. It sounds like they’ll investigate the ‘case’ and rule on what happens. This doesn’t really inspire confidence, and really doesn’t seem too favorable for the seller or for myself.

Is this a standard thing? Is there anything else I can do here? I’m used to Amazon providing a prepaid return label — this seems much more unusual, risky, and costly for all parties involved.