I could possibly see Riff and Levander having met before, like if Riff went to her school before he graduated or if they met at an event before. If at an event, I can't see Florence taking Levander with a boy too well why, what a nice pistol you have there...
I can see Riff, Rafe, or Psyche having bumped into Lyon before. Based on the TMI thread, we already have an idea how Riff and Lyon react around each other so even if we don't backlog, might be neat having someone who knows exactly what type of person Riff is? Psyche would probably only know Lyon through Order/Pro-Entropy business, which would probably something that'd put his morals/sympathies towards teens to test. Rafe, she might have met him or Rene pre-operation/pre-contract and then met him again POST-contract for mutual awkwardness/angst.
Psyche has a decent chance of knowing Remy for infoswaps, though considering personalities, how much they actually know each other is debatable.
Dominic+Psyche we already know and I'll have thread up when can~