Big fan of Divergence for Movie 5 personally!

My suggestions:

6 - Assessment/Determination/Commitment (any one of these)
Cassian and Syril both assess/determine the value of the Ghorman front for their own respective organizations’ goals, Wilmon’s determination is tested by Saw, Davo Sculdun assessed his collection which requires Luthen and Kleya to infiltrate his party, testing Lonnie’s determination

7 - Genocide
Perhaps the most important single word uttered in the arc (or alternatively if that’s too on-the-nose, something like Collapse/Catastrophe/Undoing/Massacre)

8 - Messenger
The core of this arc is about Luthen’s message making its way to Yavin 4, but on top of that Kleya sends out a desperate message which Cassian responds to; Most importantly, Cassian completes his journey by the end of this arc, on his way to becoming the Messenger the Force Healer foresaw him to be.

9 - Stardust 😉