Re: Surviving Vulcan Elders.
He didn't mend any timelines in ST VI. There was no alternate reality or timeline in that film. He just helped relocate some whales from the 20th Century to the 23rd Century to save the Earth from being destroyed.
The boring one, the one with Khan, the one where Spock returns, the one with whales, the dumb one, the last one, the one with Kirk, the one with the Borg, the stupid one, the bad one, the new one, the other one with Khan.