Not the the whole run, I obviously had no problem doing the rest, but this is all you need to do to open the door without a group. This is normal, because even if you could solo vet it would take forever for almost the same stuff. The 2nd lever within the 2nd locked door next to the boss is what triggers the door. You can get there after you pull the first lever on the opposite side of the first door, kill Drodda (the boss) through the 2nd locked door, wipe afterwards, teleport to the wayshrine, go through the portal, turn the 2nd lever which opens the 2nd door, and finally the door you need to continue should be unlocked as well. Could've shown the door and finished the run, in fact I did finish it and got only got icefurnace that time, but these are all the mechanics you need to know the rest is just DPS work. Also only wipe where I wiped near the troll or it doesn't always work, that is what I meant when when I said all that stuff after opening the last door.
The Elder Scrolls® Online: Tamriel Unlimited™