I know the campaign has already end. In case you didn't complete the campaign or is interested in someone's approach, here is a video walkthrough I pulled it off of youtube.
Campaign 2: Part 1 (Mission 1-23 Escalation on Dandoran) 3 Starshttp://youtu.be/XPIL-gj4n10
Campaign 2: Part 2 (Mission 24-46 Escalation on Dandoran)http://youtu.be/Aiim59Gw9LA
Campaign 2: Part 3 (Mission 47-56 Escalation on Dandoran)http://youtu.be/3NlMC0UXtCg