Moor sounds like a bug. Such missing NPCs (particularly the flying fortress generals and a couple others) was a moderately rate bug in DKS; it is much less common in D2:DC, but can still happen.

In Ragon's cave, there is a set of pressure plates that need to be activated in sequence to lower the barrier.

For the troll cave, there are 2 paths that lead to the barrier, one has a couple platform thingies on the ground on the opposite side of the barrier, and one has then on the near side, which you can reach. The latter is the location where the troll runekeeper should be.

Email a save before triggering the conversation with Moor to, and I can likely fix Moor's location, and check out the two caves.

With the Developer's Cut version of the game, you might be able to load the save in the Developer Mode version, hit F11 and use the cheat window to teleport to Moor, kill him, collect the loot and then teleport out (presumably he clipped below ground, so I'm not sure if you'd be able to attack if you can teleport to him).