While they waited for the other group to return, Finn decided to ask Zelestria about what power he obtained from Yokru.
[Yokru's special ability was actually built into that ring Iris has.]
That was the response he received.
In other words, he could also control those knights Iris could, but really, such an ability was somewhat useless. If he did suddenly control them, the other Ghost Hunters would be suspicious of how he was doing it when Iris had the ring. This ability was pretty much useless to him, quite unfortunately.
But according to Zelestria, the other boss was basically Yokru but as a Phantom, and had the same ability as him. Only… instead of knights, they had archers to deal with, while the Phantom boss was doing the melee attacks. It was essentially the opposite of what happened with Yokru and the knights.
Soon after, the other group returned.
Or rather… some of it.
