Got galled from the threads being messed up at the beginning.
Fix threads, anti-sieze in them and run the nut back and forth, it'll clean right up.
You do you man, some of us have fixed worse because that's what it takes sometimes. That one is nothing.
If I'm reading him correctly I believe there's damage that we're not seeing in that one particular photo, though everything you've said is tried and true, and I speak from experience. I've also spoken with doood on numerous occasions and I get the feeling that he's neither inept nor a frivolous buyer, so I'm inclined to believe him when he says it can't be saved. I'd like to see more photos of the damage but if he's like me then he doesn't want to answer questions right now, and it seems as though he has a solution in mind already.