Yeah but they weren't used to lightsabers so how would they hold up against that? They didn't even know about lightsabers...
Anyways, Pall is an unknown here.. Tulak is unknown too, all we know however is that what we know of Tulak suggests he's greater then Pall. Ragnos will take Sadow there is no doubt about this.
Now will Pall beat Tulak? Possibly but I doubt it, Tulak was seen as the greatest duellist ever, all we know about Pall is that he created a powerful sword. Thats it, a very powerful sword a great sword but that is all we know. Nothing more. We don't know a lot more about Tulak but still something, and to me thats really all that matters. So Tulak will beat Pall. Based on the little info we have.
Then its Tulak against Ragnos... Marka Ragnos an ancient and feared Sith Lord against Somebody who fought countless of Jedi and Sith in his time, now who will win this? Its clear that Ragnos was feared for a reason he must have had amazing power, more power then any Sith anybody had ever seen until that time and on the other hand we have Tulak Hord one who actually fought people with a lightsaber. Ragnos also fought but only Sith, powerful Sith Lords probably but no Naga Sadows. (I know Ragnos would cream him, its just to say that the most powerful people he fought were probably not as powerful as Sadow was)
I really have no idea who would win in this fight, there are just to many unknowns. We know Ragnos was incredibly powerful, we also know he just had one hell of a fight against Sadow. We know that Tulak is the greatest duellist ever, we have no idea how tough his fight was. We do know he is going to fight one of the most powerful Sith Lords if not the most powerful Sith Lord ever in just a few seconds.
Honestly I have no idea who will win this, I'm just going with the Ragnos team because I personally maybe without any good reason believe that Ragnos could still defeat Tulak after just beating Sadow.... I must say again however that I have no real reason to believe this and is more just a feeling then anything else, and I think the same will go for most other people here. We don't know enough about Ragnos or Tulak or Pall to make a real decision here that will actually make sense.