Just a warning to those of you on the final stretch of receiving the Sleeper Simulant: do NOT run an alternate version of the S.A.B.E.R strike before attempting the level 42 quest version the gunsmith gives you. This may be a very rare anomaly but i want to make others aware that this can cause the quest to not drop at all. This happened when i ran the level 40 timed version of the strike. I proceeded straight to the tower upon completing it only to find the gunsmith had no quest for the Simulant version of the strike. And yes i had completed all the prior steps.