I appreciate all the concern, but there is some good news. I was able to act fast and the unconfirmed transaction was spent back into my control. You can read about it here: https://twitter.com/mikeinspace/status/1369090274480300036?s=20
Unfortunately, I did have to pay someone to construct the new transaction for me on very short notice, as RBF wasn't enabled, and had to put a very hefty miner fee on the transaction to get it included in a block hours after the initial transaction entered the mempool.
In all, I'm out about $800.
I hate to do this to a charity auction, but if I can rescind my offer, I would appreciate your understanding in the matter.
I really hate to do this, but I'm still shaken up by the experience today of getting scammed and probably shouldn't be spending more at the moment after wasting $800 today to save the larger amount sent to the scammer. @M-BTC I hope you understand. I know its poor form to pull an auction bid like this. Sorry, I fucked up.