I agree with what Sharnita and NyaChan have said, the auction item was specifically a Thanksgiving Turkey Dinner from Deli -- not just a $50 gift card. Lots of places around me sell a preset Thanksgiving dinner and of course it needs to be picked up before Thanksgiving is over. Turkey Lady certainly shouldn't have picked up the dinner -- that is stealing; but for all we know, she took it to a homeless shelter not ate it herself. If that was her plan all along, first off that's just bat-poo crazy (buy a dinner pretend to donate to charity then steal it back -- why?! If she really wanted that dinner, well buy it and take it home), secondly she certainly gambled big on not having a TG dinner at all if Sister had been more observant.
I'm very surprised though at everyone saying Sister should get a refund from the church. This was a charity auction. Items are donated. To me it's no different than if someone donated a poorly knitted sweater that unraveled after one wear -- you don't take it back to the church and demand a refund or exchange for your "purchase". You might learn to be more wary about bidding on items, but a charity is not the same as a retail store with a warranty or refund policy. Sister can certainly let them know about the shady donor and problem with the deli to prevent future issues, but to expect the church to refund a donation because she isn't satisfied by the deli is outrageous to me.