I logged on last night after work to do the roulette's quick and did the guildhest one fast enough but the dungeon one was a mess...

Got Stone Vigil, 1 of the DPS immediately left while the Tank was viewing the cutscene, DPS was replaced and Tank DC'd and after waiting for a reasonable amount of time the remainder of us left... only to get hit with a 30m penalty.

Are we suppose to sit in a dungeon waiting for a tank which could take anything between 1 - ?? min to find while the dungeon timer is ticking away and we cant do a thing while we wait ?
How are we suppose to leave 'properly' so we dont get punished ?