Forgetting the whole communication contradiction, the TV broadcast was delayed by 10 minutes, which obviously would prevent Jinwoo from reacting in real time, if he was only relying on that. It would explain why he was only reacting so long after things started going south. Perhaps even if he can communicate with the ants hiding in people's shadows, he wasn't doing it before, only watching the broadcast. When things turned bad in the delayed broadcast, he would then rely on the ants. That would, more or less, explain why he didn't seem to act a minute too soon. At the end of the day, since he refused to join the expedition, it would be kind of hypocritical to monitor it in extreme detail. If he's so interested, he should have been there. This way is more honest, in a certain sense.