As for what I would suggest. Things can only consistently work if the precognition is limited. Particularly to their point of view or one close. How do you keep them from knowing that their ability is going to be used against them?  I would engineer a situation where the leader actually gets saved but the saving process puts him in an longer road to a definite capture. They may be able to foresee their own deaths, but if the leader is saved this won't necessarily matter to the same degree. If its hard to recognize a precog situation or tell how they really will play out or they take time to experience, you could attempt to "spam" their mental inboxes, especially with someone on the inside to monitor things. The more work they have to do the harder it will be to do it. Superhumans are still human.