Looks like a dent to me. In the magnified view, I can see the mark trailing off horizontally across the neck, which is not where a crack would travel.
What are you to think? That the seller is an A-hole who either knows nothing about instruments and can't be bothered to look at it, or knows what he's doing and is either hiding something or simply doesn't give a s**t and knows someone will buy it.
Incidentally, there's something a bit nasty about that output jack - the finish around it is lifting. Looks to me like either it has gotten wet or something has yanked that output jack sideways pretty hard.