"Vid transmitted open-channel to viewscreens," Cassian confirmed, more to himself than to Finnick. Didn't think Finnick would care about Cassian's terminology, nor particularly trying to teach translation (as with Jyn and Basic to Yaval). Just (hopefully) demonstrating that he understood after all and cementing the equivalences into his own mind by reinforcing with speech. The same tech or close enough.

"So the blanket surveillance is limited to the arena… Not everywhere in Panem?"

…Which means—which makes perfect sense to Finnick's worldview—Finnick must think this is an arena.

Cassian didn't feel particularly good about it, but the sick heaviness in his chest felt like he may have cracked it.