Tzenkethi Battlezone Doesn't Reward Protomatter Microcontainers half the time

tesseracttoxx

I can stay and fight all 3 dreadnaughts but the battlezone isn't rewarding protomatter microcontainers when they are all defeated half the time. What do you have to do to get them rewarded? I even pull the shield thingies out to where they are supposed to go and still no protomatter microcontainers.