: I think the Floodified Arbiters would have been later in the game, maybe a
: boss on... Huh. Come to think of it, the Arbiter never returned to High
: Charity after the Flood outbreak. Barring a major script revision, the
: only way he could have fought Floodified Arbiters is right after that
: cutscene.

It's a very strange notion, would the hierarchs import Flood into HC just to test Thel? Seems unlikely. But you can consider an idea even if you, later, decide against it.