IIRC, both these areas respawn a game year after your first visit. Has there been time for this to happen since you placed them?
If not, then I suggest you visit Sweetwater, Kriegspire, and Dragonsand to place the other 3 and check back in Blackshire to see if it's worked. If not, then I suggest two things.
First, check the chest to see if there are any statuettes in it.
If not, then exit the game, find a copy of Elrond's Editor and edit the savegame to change a couple of items in one of the characters' back-packs to match the statuettes for Bootleg Bay and Mire of the Damned. After you've done this, be sure to to pick up and replace every item in that character's back-pack in order to refresh the game memory of how much space the item occupies. If you don't do that', you'll lose things.