The LK tank will has three points (in a straight line, not a triangle) at which he tanks at. Each time ghouls are spawned he'll pull the LK to another point dragging the melee along with LK out of where they're spawning to avoid melee AoE, allowing me to come in and pickup the new ghouls. The trickiest part to this timing the shockwaves as to not let one mow down the rest of the raid. There is a cast time on the shockwave and the direction is not set at the beginning of the cast so you can somewhat guide the direction of the shockwave while its being cast.
And yes, I was on LK the first couple of attempts and he constantly readjusts.