So what EXACTLY was Plutarch's plan?
This is yet another one of those weak fictional plots that a big plan works SOLELY because it does. Not because there is any sense to it.
What was Plutarch's plan to get them out? He certainly didn't plan everything that happened during the games to keep KAtniss alive. And even more so, he had NO WAY of knowing that Katniss would shoot the force field and short out the cameras, etc. And without that, the plan wouldn't have worked.
If he just wanted to get them out, as the head game maker, he could have done so almost immediately, much safer, and then gotten the hell out of there himself (as he obviously had to do anyway.) But no..we had to go with the whole "It was BETTER if you didn't know!" bullsh**. (Hey Hollywood...or terrible book writers...no plan is EVER better with the main person involved in the plan not knowing about it.)