I was told by my supplier that GN (India) don't give warranty for the edges/toe and offer no cover for "wrong shot selection". The damage is quite extreme you are right, never seen anything like it for a first net.
Same, so this leads me to question if there's an issue with the bats too rather than just the prep/usage. It's extensive damage and maybe due to drier willow, manufacturing, hidden issues. Then compounded by poor prep, cheap balls and misuse. I'm not having a pop here, just speaking from experience of a few brands who I've spoken to who had switched to new suppliers, as they'd been down the route of buying bats from cheaper suppliers and found it was giving them more headaches/costs in terms of returns etc. So wanted to have more control of the production/buying side more, to lessen returns/issues but also have some recourse to their supplier if things have gone wrong. In the same way, I'm sure UK retailers who demand support/warranty from brands etc if there are issues. If you're buying bats from India cheaper than you'd get them elsewhere, then you maybe won't get the same level of support maybe.
As
@KettonJake mentioned, returns are part and parcel of being a maker/retailer. Sometimes, even though you may feel a bat hasn't been prepped correctly etc, you can't prove it. So your choice is you take the hit, or alienate a customer and get a bad name for service/quality. Just chalk it off and go again imo. Maybe look at the supply chain if u have no comeback and your route to market (eBay isn't great imo due to lack of control you have, as this demonstrates). However, with the amount of dodgy stuff sold on eBay, it's maybe necessary from a consumer safety pov. I bought some golf grips recently which were obviously fake when I received then. Got a refund straight away, which obviously worked in my favour.
This was why I asked about your returns. If you were selling through your business site, you have more control of the returns process and could offer a repair under warranty, or replacement. Both options leave you not so much out of pocket. Obviously, there are then other costs to factor in though.