<Yep. I also did the tiles and sprites of the Goblin encounter.>
A distant voice from one of the cells can be heard. Its arrogance boasts, "How does it feel to sit here with us, huh? Not such a hard-ass prick now!? What was it you called me the other day? Huh!?" Whatever is going on is interrupted by irritation, one of the ogres bursting, "Quiet or I step on you like warg's crap and wash off in river!!"
Upon further examination of the ogres, even they seem to have spears ready and seem to be the one carrying the keys on them. As for the cell doors, they appear to held in place by a brace, which in turn is forbidden removal by a bolt lock held in place which can also be picked and removed.
The door in the back is easily unlocked as the others, and it is possible to look inside while the ogre is turned away. It is dark, but the light from the outside reveals an abandoned war game table, the kind of which has miniatures placed upon crude map drawings and cards are drawn to determine random chance. Whoever was playing this game was pulled away while their White Mage Cardassian was healing the Highlander Muggle in their struggle to fight a high level priest of Ra in the fictional sun bathed setting of Egypt. It seems this would have been the room the keys would have been stored in as evidenced by a rack to hold the rings, but obviously the ogres have decided to carry them on them instead. Other items within the room are mostly miscellaneous supplies.