ICC: Icecrown Citadel Confusion

So I find the narrative of the Deathbringer Saurfang encounter confused. If I am making sense of the first four bosses of ICC, the Ashen Verdict made the initial ground assault on the Citadel, gaining a foothold. From there, a “group of adventurers” is able to defeat Lord Marrowgar and Lady Deathwhisper, where they ascend to the Rampart of Skulls to find that the Skybreaker and Orgimm’s Hammer have air dropped troops onto the Citadel, and naturally begun fighting idiotically at the worst possible time. The Horde and Alliance push their way to their respective ships, where they take off towards Deathbringer’s Rise to gain entrance to the Upper Spire.

Here is the confusing part. Along the way they encounter the opposing faction, and engage in battle. Both sides claim to have defeated each other and moved on to defeat Saurfang. If you read the dialogue from the Deathbringer encounter, it isn’t possible that both accounts are completely true. In one Saurfang shows up first and the Horde defeats him. Muradin does not appear. The Rise is manned by Horde personnel. In the other, Muradin shows up first, the Alliance defeats him and Saurfang shows up after Deathbringer is dead. Alliance personnel man the Rise.

Now, I get that there can be conflicting accounts of the same event. I think this is a fun way to implement the acting out of the narrative. The problem with the Gunship and Deathbringer part of the story is that since one account precludes the other, its hard for me to imagine a situation where both sides could think they got there first and had no help from the other faction, and both claimed the same spot.

Working together or even tolerating each other sounds really unlikely considering they were just attempting to kill each other, even as the Scourge was trying to kill them both. The only way I can really see this happening is to say that somehow, neither side ever really stopped fighting with each other. The "victory" in the Gunship battle was just a momentary lull in the fighting, and the other side retaliated. They continuously skirmish over Deathbringer’s Rise after Deathbringer is defeated. The “group of adventurers” took it upon themselves to not bother with the Horde vs Alliance nonsense and take out Deathbringer. This makes sense, given the pettiness of the fighting they’d been doing.

But this still doesn’t explain how the characters would experience things in such a way that both sides claimed they were the only ones fighting Deathbringer. I don’t see any explanation.

Oh wait!

The Gunship battle, if I am interpreting things correctly, is put there as the result of the Wrathgate when the Forsaken betrayed the Horde and the Alliance. King Varian Wrynn would not forgive the Forsaken (though it is not clear to what extent the Forsaken as a whole were innocent in the whole affair) and declared war on the Horde during the Battle of the Undercity. The two factions had already seen rising tensions and skirmishes, particularly in Grizzly Hills.

By the time they reached Icecrown Citadel, they were in open war. See the quests in Icecrown that involve Mordre'thar: The Death Gate. But the problem is, the war effort against the Scourge is severely hampered by this pointless conflict, for obvious reasons. On each gunship you have Argent Crusade representatives telling them to cut the crap and focus on the Scourge. Thassarian and Koltira, Ebon Blade questgivers, are pissed about it too.

This is part of the motivation behind the Argent Tournament - to get the two factions to work together, because if they don't, they cannot defeat the Scourge. It works partially, but the relations devolve back into bickering and fighting on the Rampart of Skulls, leading to my current question.