After many tries and failed attempts I've got a workable strategy for a t2 Ruined City run that does NOT involve killing either of the first two bosses or the majority of the trash pulls, thus cutting down on time consumption.
Starting out (entrance to first boss)
Two strategies here: First strategy-run straight by EVERYTHING until you get to the door with the lever that leads into the large arena where the troll boss is. If you attempt this method, I suggest not buffing except for using coffee for the 10% run speed boost (no food, tokens, scrolls). All 3 members will need to stay close together, with the tank leading to get aggro. The healer should be spamming heals as everyone runs through, otherwise you won't make it, and as long as the tank is using taunts properly the healing should not draw aggro. When you run past the first boss (the haradrim) the quickest way past him is to run straight through (keeping him on your right side at all times), jump off the broken bridge, swim to the right, climb the stairs, and keep running. When you reach the troll door the tank needs to kite for about 2 seconds so the 3rd member of the group can pull the lever. Don't use the tank or mini for this portion, the mini may need to keep healing b/c there will be about 20 mobs around. As soon as the door opens, all 3 members should run through, and the tank and dps classes should give themselves up while the healer uses their flop skill. So, tank and dps members die, mobs think the healer is dead, all aggro goes away and all mobs from the first part of the instance will leave. When they're gone, mini can pop up and rez the other two.
Now, you're at the troll...easy to bypass this guy too. You will see two archers, with a captain walking back and forth in front of you, and a large piece of siege equipment to the left. Have the mini distract the archers and/or captain, and have the tank lead a run along the left side (stay next to the siege equipment as you go) and circle around to the gate on the far side. You will draw somewhere between 3-5 mobs as you make this run. When you get to the gate stack on it and it should open after a few seconds, at which point you can go through and kill whatever trash you've picked up. Stay to the extreme LEFT on the path ahead, as long as you do you can safely bypass the next two groups of mobs without drawing aggro. The third group of trash led by a half troll you will have to fight; not difficult to take them down. However, on t2 at this particular trash pull a fell spirit will appear BEHIND you during the fight and will start hitting either the mini or dps class (healer most likely) so have the tank ready to go pick up aggro on that. After they're down, continue forward and you'll only have on pull between you and the final boss. Kill that group and head to the palace. When you get there have ONLY ONE (not the healer) of the group enter the palace and trigger the fight by themselves. They will, of course, die, and the boss will reset. This step prevents any strange glitches going forward. When the first member dies, the others may enter and rez him.
Now, details on the boss fight... The boss has a debuff that does -90% outgoing damage and healing and it has a large radius, so positioning is very important. The dps class and healer should stand on each side of the landing just inside the entrance to the palace. The tank needs to tank the boss in between the 4 pillars with the flames on top just at the bottom of the stairs where the boss is standing before he's triggered. When the boss hits the debuff skill (boss screams and you see a purple cloud) the tank will get stunned for a few seconds and will drop all aggro while stunned, so the boss will alternate between running to the healer and dps classes and hitting them 1 time. Nothing you can do about it, just have to take it. If your morale is below 16k you will be 1-shot, this guy hits HARD. So, for the healers, be mindful of this and be ready to heal up either yourself or your dps member when this happens. At two different points 3-4 shade adds will be summoned. When they drop, it is the dps member's responsibility to kill them and then go back to hitting the boss. When they appear the tank should taunt any that aggro on the dps or healer members. Of the adds, there will be 1 each wave that has a buff that dramatically mitigates damage it takes, so I suggest killing this one last; watch the status bars on the shades to know which has it.
To complete the challenge...there will be 2 yellow spirits that spawn at different points during the fight; more annoying than anything. Again, tank needs to keep aggro on them, and to complete the challenge both of them must live through the encounter. To minimize their effect on the fight, have the dps and healer (if they have mezz/fear skills) take turns mezzing/fearing the spirits. Also, no AOEs after they're up in order to not accidentally kill them.
And there you have it, that's all it takes to complete RC t2! Enjoy your crests!!
As an aside, if you find the group is dying while running through to the troll gate, here are the trash pulls that should be killed: all the trash up until the first boss (then use the strategy above to bypass him). If you get by him quickly enough he and all his adds should stop chasing after you get to the bridge where you first see the mordor orcs. At this point, kill the next 3 trash pulls (stop killing when you see the group with a defiler). At this point there are only 3 groups between you and the troll gate, so you should be able to run through and use the strategies above.
Any questions/additions please comment below or catch me in-game.