Followed up on this:
Shaytherrin the exorcist gives 3 tasks.
The Dark Tower: Flickering Torches - Get 10 Torches
The Dark Tower: Fallen Guard - Get the emblems from the two sergents and the chaplin, kill 10 guardians
The Dark Tower: Lord of the Tower - Kill the Captain. (He teleports upstairs halfway through the fight). Can choice from 1 of 5 items when complete
However in the room with the chaplin there is a little skull and crossbones chest. Nothing happens when you open it - shrug - still not solved the remains task.
Cheers,