There's something I just realized, the deleting pic thing doesn't really work unless you also take their phone for a month.
To clarify, when you delete a picture in your phone gallery it goes into the trashcan, you can access the trashcan from the in app menu -on my Samsung Galaxy it's the three horizontal lines at the bottom right- and they will be there for 30 days where you can un-delete them. So you have a whole month to pull that blackmail material from the trash.