Possibly, but it's likely that to much blood has been spilt. As Skolas says [quote]Remember the City of the Death of Children, the City That Docks, which claimed for itself the Great Machine that might have saved us. Remember the City that even now sends its ghouls to murder our Primes, starve our ether, and leave our young to die gasping. Curse that City and its name. The curse is just.[/quote] Also it seems Uldren may have taken control of the fallen. He wasn't overly friendly towards Guardians.