Claw of Jormag not spawning.
The fact that Icy Runes aren’t purchasable isn’t evidence one way or another; there’s almost always been a map in which Rohan doesn’t appear.
In terms of the pre-events, were the four initial crystals destroyed and did the fifth appear after? Did you happen to check the time remaining? Did you happen to make note of the /ip of any of the maps?
I was on a map (a while back) in which the fifth crystal didn’t spawn until the timer was nearly expired; we just barely managed to clear it in time. So I imagine it must happen sometimes that the events fall short of causing the Claw to appear.
John Smith: “you should kill monsters, because killing monsters is awesome.”