The Vulcan stuff is in the story, since Spock goes through some ritual that reveals his eventual death to him, which leads him to rejoin the ship when it goes back out in search of the titans.
But whether that stuff is Vulcan or the titanplanet ... it doesn't look like the awesomeweird stuff Adam drew for the space brain on the titan planet, which was like giant rock candy in a way (others have said Liebskind the architect seems to have borrowed from Adam's titans stuff.) But it doesn't look vulcan to me either.
Are there any other pieces of art?
You've obviously seen some pieces I haven't, and I've never heard this thing about Spock seeing his own death. Where did you pick up those tidbits?
I'm almost through the art I have that I can confirm as Titans stuff. I have some bits that I'm not sure where they're from, so I hesitate to post them for fear it'll contribute to incorrect folklore about the film.