Seller: PSA accidentally bidded on the wrong card.

I recently went on eBay looking to buy a PSA 10 Boa Hancock PSA Magazine card. While browsing, I noticed that PSA was running an auction for one, and the bid was already at $255. I mistakenly assumed the slab was a PSA 10. It wasn’t until I got a notification that I was winning the bid that I realized the card was actually a PSA 7, while the average sale price for a PSA 7 is around $55–$80.

I tried to retract my bid immediately when I noticed there were only 2 minutes left on the clock, but eBay wouldn’t let me. Now that I’ve won, I really don’t want to overpay for a PSA 7. I’ve attempted to contact the seller, which is PSA via eBay messages, to see if they would cancel this order.

In the meantime I notice a message saying "processing on Jan 8th", I removed my payment method to prevent the auto-charge while this gets resolved. I know it’s my fault for not checking carefully, but I was focused on the high bid and assumed it must be a PSA 10 — especially since a PSA 10 goes for around $380 and the auction had one day left.

Does anyone know if PSA actually responds to eBay messages, or if they can force me to pay in a situation like this?