Boreas' chest is probably not using the default Hiberheim chest contents.
For the meta file, you might also be able to edit the coordinates. As long as the characters end up somewhere within the map the game shouldn't crash, and you can use the teleporter pyramids to get everyone together if necessary, then Rift Travel to get elsewhere if you are out of the map bounds and can not walk around.
It would likely be easier to just load the save, teleport to Cyseal, resave, and then swap the new game save meta.lsb file there.
