Yeah towards the end of the ghost scan segment there is an unstoppable champion that will despawn if you kill the boss and ads too quickly and reduce the end rewards to gold.
This can be pretty frustrating when farming no comm runs and everyone is just speeding through without much thought (no problem with that ofc) Just need the champ to not despawn once the encounter is complete and it should be fine.
-
Every strike just about has despawning champs to punish inefficiency and lack of awareness