I got through the "dread" portion of the episode once only to have restart. Now I can't "kill the remaining..." because they have started falling through the floor. Two different spots on two different restarts. Actually it also happened on the planet while trying to save things. Some Guardian got stuck in a rock, half-buried...entire team stopped to kill it. Big waste of time because it to no damage...other things died while they waited for us to rescue them. I can't progress.