Would Walder betray Robb without Roose and vice versa?

[Ralphis Baratheon]

One more thing to take into consideration is that Roose was holding Jaime Lannister before the RW happened. This could have possibly given him leverage to be needed in Tywin's and Walder's plotting. 

[Foot_Of_The_King]

2 hours ago, Ralphis Baratheon said:

One more thing to take into consideration is that Roose was holding Jaime Lannister before the RW happened. This could have possibly given him leverage to be needed in Tywin's and Walder's plotting. 

Good point

[Chris Mormont]

To answer your original question, while I think Walder would have betrayed Robb without Roose, I do not believe he would have orchestrated a Red Wedding type of betrayal.  I definitely agree that Tywin's amnesty and protection was a deciding factor and required not only Robb's head but the destruction of his army.  But without Roose, I don't think he would have had the guts to go through it.  He probably would have thrown them all in a dungeon, pulled his men from the field and sat and waited for Tywin to come and collect them. 

Roose, on the other hand, was subtly betraying Robb probably from the beginning,and definitely after NEd was killed.  He knew if he continued to follow orders, he could weaken all the other Northern houses and Robb would take the blame.  He could play a little politics, determine who might be willing to join him and then strike when the time was right.  

[Kandrax]

5 hours ago, Chris Mormont said:

He probably would have thrown them all in a dungeon, pulled his men from the field and sat and waited for Tywin to come and collect them. 

I think this would happen, had Robb not married Jeyne.