I was actually wrestling with whether using Marek or Mace Windu (Vaapad). So since some of Marek is unknown swap out Marek for Mace Windu with the Vaapad........
And the the fighting would go (IMO) like this
Darth Maul engages Darth Tyrannus and because of his hatred of anything and anybody sans Darth Sidious, I believe that he will eventually ware out Darth Tyrannus and show him how much of an uncivilized beast Maul is.
Anakin will now have the opportunity to act on what he was thinking when he told Mace Windu to Vaapad this in the ROTS novel. So it is the Power of Djem So vs. the Anger of Vaapad with Mace Windu eventually coming out victorius because as Windu stated in the ROTS novel, if it just comes down to Vaapad then he would be able to fight forever and eventually Anakin will lose his head and then Lose his head, so Mace Windu wins this one.
So that leaves Master Yoda vs. Obi-Wan Kenobi.......the speed, agility, and acrobatics of Ataru vs. the defensive mastery of Soresu, with Master Yoda being able to break through the defenses of Kenobi and eliminating him.
Now Yoda and Maul engage Mace, with Maul being in the place of a lifetime by having the opportunity to fight and kill a great Jedi Master, but Maul despite his mastery of the Jar'Kai style of fighting finds he is in the long run no match for the Korun Master of Vaapad, so Mace Windu brings this beastly Sith Lord to his knees. leaving now the Grand Master of the Jedi Order against the Korun Jedi Master of Vaapad and they begin to fight with the Calm and Peaceful Green Jedi Master quickly taking the upper hand against Mace Windu due to the nature of Vaapad being restricted since he is not fighting an individual that is ANGRY, rendering Vaapad almost useless and eventaully deactivating his green lightsaber standing over the decapitated body of his friend and former padawan Master Mace Windu.
YODA WINS!!!!!!!!!!!!!!!!!!!!!!