Harding Can't Interact With Stone.

During the Companion Quest 'The Waiting Stone', your objective is to remove the source of the blight and I cannot progress further into the quest simply because the pathway gets blocked by there being no option to interact with a stone that is obviously meant to be pulled out to allow Rook to jump onto the hanging wooden platforms. The first two stones work, but the last doesn't, which essentially traps you in the quest without being able to progress at all.