Spoiler :
As I pointed out in some youtube video long ago, this was already hinted back in their first encounter (with Lance). Not only the plant caring trait was present, but her kinda crude and teasing way of speaking, her poneytail, and most of all her "tag" in the Resoom / Current organisation, as Artemis addressed her as "N°2", were already pointing out in the fact she might be older and different from the actuals carriers (like, number two of what ? Certainly not carriers since they've been "harvested" for centuries).
The new interlude just cemented the fact out of mere hypothesis once and for all by bringing new hints about her father and Damion. There's now too many hints to even need her to be addressed as Diana anymore to confirm it.