I know enough to conclude that No Stormcloak Rebellion = No Imperial ambush = no PlayerChar getting ensnared by it as well.
http://img844.imageshack.us/img844/8260/3mc1.jpg
Dragged along for the ride to their execution, and nary a word said to disavow the side-catch. "No point, they wouldn't believe a Stormcloak"? But the effort would have been made and the blame would then solely be on the Imperials. But they didn't, so we'd never know. There were record anomalies with PlayerChar, and combined with "PlayerChar there is side catch, you gonna off an innocent, Imperial dogs?", it's a case to at least set PlayerChar aside to figure out what's going on.