OK, let me get this straight. Meg was in Miracle months ago (before she joined the GR?) with her fiancee, right? And that's when she met Evie and told that knock, knock joke.......And then several months later Evie tells the knock, knock joke that she learned from Meg months ago and then disappears to the GR. And then Meg comes back to Miracle.
Is that the right sequence of events? Sometimes this show is confusing with it's un-sequential episodes.