if you didn't take photos before you sent it back then nobody to blame but yourself, unfortunate but just remember in case you need to send one back in the future.No shit sherlock...so the question is....who bent the pins? I cannot say 100% I did just as B&H cannot say they 100% did not.
The only way I can think i bent them is if the plastic protective cover bent them while packing mobo back up to ship.....but there is about a million ways I can think of how they bent them.