The last ability causes creatures your opponents control to lose hexproof and indestructible as it resolves. Effects that cause those creatures to gain those abilities after that point will work normally.
Damage dealt to a creature with indestructible is still marked on that creature. If that creature loses indestructible, and the marked damage is lethal, it will be destroyed. However, if a creature with indestructible is dealt damage by a source with deathtouch and then later loses indestructible, that creature wonâ€™t be destroyed.