Hello Shadow,
When you have time could you please check the NPC in front of Market Town in Hellbound. It suppose to let you in for a 30 min instance so you could find a key and enter in Steel Citadel. Usually the requirements to enter is only party of 2 (lvl78) and Premium Certificate. I have them. Still this NPC won't let me in. And that is the only way to enter the Steel Citadel and meet Beleth. So please check it out.
Thanks.