@hrs6gm : I mean, if he's the...'kind' type, he might say let them die.
After all him reviving them would means they're going to kept being 'farmed' by Rose and others.
@Gudachiz : But why give them eternal death, when he can revive them over and over for them to suffer.
Since his side get to decide if/when/where to revive them, he can ensure they don't ever have any chance of escape/fight back and keep using them as long as Licht keep reviving them.
Hell considering he revived everyone here from practically out of thin air, even if the girls get a bit rough with their body he should still be able to revive them.