It seems as though the two chests there are not functioning properly. It has been a year or two since I've been to the dungeon but I don't remember having to do anything special to open them.
They had "special key required to open this object" when I went to pick them.
Then I bashed it and got DC: '-178956950" and was able to open it.
It is worth noting that the Area did not have a single shadow in it. So either the area as a whole is bugged. Or there is nothing wrong this is the equivalent of a "bat spawn" in the caves where there is nothing, and the DC is set low intentionally so that anyone could open the chests.