Escalate to the Claim.
Ask in the claim if the attached pictures can be substituted for the broken item.
The reason for the item to be returned is, while most people are honest, there are buyers who will claim damage or other problems to get a 'post-purchase discount'.
When the case is resolved, whether you win or lose, neither of you can leave feedback.
If you can afford to drop the case now, (and think about what your financial limit is on this, not your emotional one) you can leave feedback to warn future customers.
The most effective feedback is calm and factual. "Item disintegrated on arrival. No refund or resolution offered.' for example.
At the same time you will be asked to leave Detailed Seller Ratings. These are MUCH more important than feedback, which is rarely read or understood.
A normal 'meh' transaction should get Five Stars. If a seller's stars drop belowe 4.3, her ability to list and sell on eBay may be restricted, her fees may rise, or she may have her selling account closed.
The lowest Rating is ONE Star. No stars is a free pass.