The finding that two RNA molecules would have been sufficient to start life, seems a little like the idea that has been proposed of an RNA template and its complementary copy originally functioning as an informational/functional(= ribozymic) pair (see for example: Shay JA, Huynh C, Higgs PG (2015) J Theor Biol.
Fig 8 is very reminiscent of Fig 1 of Wu and Higgs (2009) J Mol Evol 69:541-554 and Fig 1 of Wu and Higgs (2011) Astrobiology 11:895-906.