There are no main jobs in my journal after completing search and destroy. I read somewhere that it might have been because the whole act where you find soul killer is bugged and never lets you actually do it. I myself only got to finding and talking to alt cunningham's construct and assumed it was the end of that act. I however received a mission asking me to talk to Jonny after this act but his dialogue didn't make much sense in the context of the story. I think that it might have been an out of place mission that bugged my game so that I could not play the soul killer act. I've invested a whole lot into this game time wise and this bug really ruins it for me. I hope they come out with a fix soon.