If this match goes to a third match, Steve Austin wins it. Not because of it being a Ladder match.. but because of it being a question of endurance. (*awaits Irish to dispute this*)
I have perfect proof that Vader can't handle a match going too long.. look at the Summerslam match, against a much smaller, much weaker, Shawn Michaels. Vader controlled the early parts of the match.. easy.. he dominated Shawn, forcing a countout. The match gets pushed to continue, because Vader wants it to.. so be it..
Due to Cornette, the second half of this original one-fall to a finish match, ends in a Disqualification.. once again, in Vader's favor. Shawn Michaels has been beaten within an inch of his life, Vader has barely been touched.. so he requests the match continue.. his request gets accepted.
The final portion of this match, the much weaker and smaller guy.. ends up winning, with a Moonsault.

How is it, that a guy Irish has been promoting like a mad man, with missing eyes, and beer belly's.. lose to a sloppier version of his own move?! Simple.. he was gassed.
Thus.. you have to eliminate the third match from this aspect, because if it goes that far - Austin wins, automatically, just on the note that Vader won't last through endurance.
So, we look at the first two match-ups.
Hardcore Match: Austin gets the upper hand here. Why? Just because Vader's a bad-ass, doesn't mean Austin isn't. Irish flip flops on the footage he shows us.. but when exactly was Vader in his prime.. that's the question.
Austin was in his prime, when he was arguably leaving E.C.W, coming to the W.W.F, or possibly when he became Stone Cold Steve Austin. It's during this stage in his career, he was the most violent, brawling, "toughest S.O.B" there was. So how does a guy the size of Vader.. hold up, against a guy like Austin, who'll stop at nothing.
Somewhere there is a Vader v. Steve Austin video floating around.. I think you'll see Austin has more of a dominance advantage over Vader. (of course, this was during a time I think Irish believes Vader was falling out of his prime, while Austin was just entering his)
Steel Cage: Is it pinfall, submission or escape through a door/over the top? If it's just old, old school - over the top only.. then Austin wins two straight, no need for a third match.
I've never seen Vader climb a cage. If Irish can show me even the slightest footage of Vader climbing a cage (much less out of one) I'll change my opinion, and say Vader will own Austin inside a steel hell.
Regardless, I'm saying this.. Vader will own Austin inside a steel cage.. but unless it's pinfall, or escape through a door.. Vader has no chance of winning. He could knock Austin unconscious and still not find enough time to seemingly climb a cage in my opinion. (but I'll await proof that he can, before I fully say this)
In the end.. I told Irish I'd likely vote Vader, because I despise Steve Austin.. but the truth is.. if I'm doing this fair, Austin is slightly getting the advantage of my vote - based off the match that drew in both men's favor, or disadvantage, as I see it.