That's not a crack, unless I can't see what you mean. There's a sliver of something standing vertical but if he cleaned all that off for us it would provide a different picture.
I see the rough, dirty appearance and agree it needs a good look. I can't for the life of me make out any heat discoloration though... I wish he's clean and oil and come back with new pics. The bolt head, well...if we could get our noses over top it might be different. Completely agree about better pics and if he understood what you wanted it would be better, location wise.
The whole thing could be as you say, I just think there's less here than meets the eye... If he sends it off to BDL, we'll get definitive...?