This is part of the reason that I say I think that if you flee, the only White Legs that stay were those that were alive when you completed the quest.
I chose flee and while the Sorrows and Dead Horses camps are empty, I still find Dead Horses prowling around Zion.
First i did flee and i didn't see any White Legs, but after fight, Sorrows at camp & Dead Horses at camp & sneaking all over Zion
Maybe i killed all off the White Legs :goodjob: