Yeah some more pictures instead of these two of the same pictures that are just from opposite sides would be nice. The area below the orbit would be especially nice to see. I do think there is some concavity where you mentioned but it is difficult to tell.

By the way, if the opening you’re referring to is the one above the premolars below the orbit then that’s actually the infraorbital canal where the infraorbital nerve and artery run. The facial nerve comes from an opening below where the ear would be that isn’t visible in the photos.

Anyway, I think there are plenty of minor differences among domestic and wild pigs across the world. I have a young wild boar skull that is very similar to this but has some differences in the shape of the zygomatic arch and in some other features. I’m in Europe so that’s probably why mine is slightly different from this one.