Think, for a second. Is the Didact dead? If he was dead, the Prometheans would be blue instead of orange. Think Forerunner (level) Didact: Assuming direct control. The Prometheans turned orange. So if you have played Spartan Ops (I know it sucks but bear with me here) you see that the Prometheans are ORANGE so the Didact's mind, maybe as a big Promethean knight is still controlling them. And also, the Prometheans are invading Infinity when, if they weren't under the Didact's control their sole purpose is to DEFEND Requiem, not to attack humanity. Example they work with the Covenant Remnant, who set Requiem to collide with Epoloch. Well, that's all for now, if you want, write in the comments below.