me and my bro were doing a dungeon with another friend when i went to the next room (THE FINAL ROOM)they didnt follow so i waited a while :x welll i lost it and went back to get them in the last room GRRRR i went completly out of the dungeon to where the entrance was and had to do the whole dungeon again while my bro and our friend completed it....
when you entered and they did not, the game sent you to a different realm. This happens to me just going through a door aor change worlds and such. Make sure you realm reads perfect before doing anything in the game.
I agree out of all the things that can be annoying in Wizard 101, this is the most. The 30 minute reset of ALL Dungeons should not be 30 mins. I feel as a Hardcore MMORPGer Dungeons(instances) should have a longer reset. Nothing annoys us most that once we barely make it out alive sometimes on a boss fight, when we go back in the Dungeon (instance) even if it has been way under 30 mins the bosses we killed had respawned already, and there sidekicks, aswell
The time on the Dungeons(instances) need to be way, way more extended. and when we drop a boss the are no longer there until the Dungeon(Instance) resets.
If you leave by the entrance, the dungeon will reset. If you port to (or enter) your dorm/house, the dungeon will reset. If you change realms, the dungeon will reset. If you enter another dungeon (or play the mini games), the dungeon will reset.
Your best bet is to just put a marker down so you have something to jump back to.
me and my bro were doing a dungeon with another friend when i went to the next room (THE FINAL ROOM)they didnt follow so i waited a while :x welll i lost it and went back to get them in the last room 
GRRRR i went completly out of the dungeon to where the entrance was and had to do the whole dungeon again while my bro and our friend completed it....