Personally I don't think silicon knights has any grounds for the lawsuit.
I know that any time I ever posed a question to epic , they were more than happy to respond and provide answers or work arounds.
Saying they didn't provide support and withheld the version of the unreal engine used in gears of war is just trying to shift blame.
I can't say what the unreal title I worked on was, but I can't understand where silicon knights is getting the idea that epic didn't hold up their end.
To me it appears more likely that silicon knights just wasn't up to the task for using the engine they licensed and are placing the blame on epic.