Lightning
Master Member
Let's think this through. So they are currently before the timeline split. But we've never seen evidence that time travelers can come from "potential" timelines. That means the only future available is the one Picard and Co. came from. So unless they actively change it, the crew of the Enterprise D will never exist to go back to meet Mark Twain. So this Guinan never met Picard in the past. Once they stop the change she will suddenly regain those memories.