In the auction pics, i think I can see a hint of the rust, but if you look at the problems on the ponies, and then look at how they are arranged in te photos, the worst ponies are carefully positioned to hide their flaws, while still actually picturing the correct ponies. This was deliberate. It was no accident.
Yeah, I can see the issues in the auction photos if you look really closely. The seller just put the nastiest ponies towards the back and didn't use the "macro" setting on their camera so they all look decent.
If these ponies aren't up to your collection standards, I am certain you could trade/sell to someone else who would greatly appreciate them!
At least there's that...