Hmmm, interesting.
The eBay Money Back Guarantee (MBG) does not require you to put in a narrative or add a picture or anything like that , so I'm a bit confused.
If the seller sent you something that is 'not as described' (NAD) then you could go to the Resolution Center {link at the bottom of this page} and file a "case" for NAD. In that situation the seller has a few days to respond to you: either work something out, accept the return or just issue a refund. IF the seller accepts a return, they will be required to issue you a return shipping label. You will have several days to get the package accepted by the shipper and that means standing in line and getting the bar code scanned by an employee and leaving with a receipt. Once the seller gets the item back, they have a few days to issue the refund.
No where in this process are you required to provide "proof" if you file a NAD case.
It often makes sense to understand the rules of the MBG because it is so protective of buyers. Problem we see is that buyers don't read the MBG, don't understand the process and do something they "think" is right, mess up, and then lose the rich MBG protections.
So if nothing else, as you navigate the MBG process, feel free to come back here and ask questions!
https://www.ebay.com/help/policies/ebay-money-back-guarantee-policy/ebay-money-back-guarantee-policy...
