Star Trek Picard: Every Easter Egg & Hidden Reference From 'Broken Pieces'

In the cockpit of the La Sirena, Auntie Raffi mistakes the Emergency Navigational Hologram for the real Rios, despite the ENH's Irish accent.

She gets to talking to the ENH and shows him a graphic of the odd interconnected circles she discovered when she hacked the Borg cube in "Nepenthe". These are the circles that the "disordered" XBs were drawing in "The End is the Beginning" and the ENH recognizes them as a representation of an octonary star system. The ENH references a real life system, Nu Scorpii, saying that (in-universe) it has seven stars but that there are no known systems with eight suns.

Raffi deduces that the Conclave of Eight she believed orchestrated the synth attack on Mars (as mentioned by her son Gabriel in "Stardust City Rag") is in fact the location of the evil plot, not the name of the conspirators themselves. In a later conversation with another Rios-ish hologram, the Emergency Engineering Hologram, she comes to the conclusion that the octonary star system must be constructed to get attention and convey a warning.

The Emergency Engineering Hologram, by the way, has a Scottish accent, a reference to Scotty in The Original Series and possibly Jason Isaacs' impression of a Scottish engineer in the Star Trek: Discovery episode "Despite Yourself".