#jf2

Duncan volunteering to send his black lotus to Rythian as well is something that can be so personal. To over analyze it, although he says it is in case "the first one gets lost" they have no reason to think that items wouldn't get to their destined locations, so the choice reads much more as a gesture of friendship. After the events of Flux Buddies (no spoilers) Duncan has had to learn to face the consequences of his own actions in a way that he simply had not during Blackrock - which at the end of the day was the thing that drove a wedge between him and Rythian.

By not being able to accept that his actions led to genuine harm (intended or not) to those he called his friends signaled to Rythian that he cannot trust others/especially Duncan again. This perceived threat of future betrayal combined with Rythian thinking that Zoey had joined forces with Duncan and the nuke reveal all served to retraumatize Rythian, placing a wedge in their relationship that has not been able to be addressed due to the end of Season 2 and Rythian deciding to give up on any relationship (friend or enemy) with Duncan ('the opposite of love is not hatred, it is indifference' etc etc).

So Rythian choosing to send this task to the JF2 crew, almost certainly knowing that Duncan is among them, shows that Rythian has been able to grow since we have last seen him. He has been able to finally process, at least to a degree, what he has been through and perhaps is able to understand why Duncan acted the way that he did - that he never meant to cause harm but was terrified for his own safety both in the old and tekket worlds.

Duncan being the one, in episode 28, to want to listen to the message (as well as including the purple flag 'for Rythian') shows how much he has also changed. That he also understands, at least to a degree, where Rythian was coming from and why he did what he did AND that he doesn't hold that against him. All of this happening independently from each other until now. Rythian made the first move at reconciliation with entrusting Duncan (and the others of course) with a task that was important to him (but at the same time it is a task with a low level of responsibility so that if Duncan did not want to accept this peace offering of sorts, no harm would come to Rythian/Zoey). And Duncan, by sending his black lotus after barry has already sent one, is a clear acceptance of that gesture. More than that, it is returning a peace offering of his own. (and to REALLY over analyze, sending flowers is a sign of an apology with black/dark lotus flowers in multiple cultures representing rebirth).