Mirror Universe event - no final drop
 

In the Mirror universe event, once you have killed the boss (AKA ENT-F which looks very sweet in motion), you are advised to return to the star base to pick up your supply crate, or something to that effect. You can fly all around the base and there is no drop there. I am not sure if this is something to be added in later or a legit bug.

I got a drop after defeating it, but we were almost on top of the starbase, so I figured that that drop was the mission-complete reward. I haven't done it a second time to check.

Sometimes no drop :( Its a bug i get a missing drop 1/3 runs

I had this twice as well. both times it happened after the event timer had closed for new instances. Not sure if that is the cause or not.