Can't Exit Undergrowth Ruins - Is This Normal?

To start with, I know this should probably be under 'issues' and not here, but when I try creating an account they just say my browser went wrong.
Secondly, I'm a lvl 59 Assasin.

I was stuck in Undergrowth Ruins boss room when I had killed the boss. Either my Wi-Fi was lagging or it was the server (the server was almost full). I had killed the boss and I wasn't getting teleported. I didn't want to do /kill, because then I wouldn't get my rewards. So I decided to relog. Then I was outside the dungeon without a reward.

So that means I wasted a key, I only have 18 of them now. Is this normal? Was it a bug? Should I just redo the dungeon? Did I do something wrong?

 

Redo it, don't relog in boss rooms

 

Disconnecting, relogging, switching classes, server restarts, etc. will remove you from the dungeon if you were in a boss room when it happened. If one of these things is about to happen or if you need to /class, try to do it before you go into the boss room.

I think this was done to prevent people from timing a /class or DC in order to fight the boss multiple times and get multiple rewards from a single key, but I'm not 100% sure about that.

 

Wait till you get to Fallen Factory (Level 90), the boss fight is extremely long compared to other dungeons and also has multiple rooms as well