logbook Area contains 1 addional afarud commander somtimes not spwaning

In the some logbook i would say every 5-10 tryes there is one where even after exploding the commander mark, "nothing" spwans ? or atleast only a rare spawn? im unsure what exactly comes out. but what i can tell is that no unique enemy spawns.
so far in a sample size of 20 i had 3 logbooks without boss.
They all had the Modifier and in all of them i exploded the boss marker.

Bug Report ID: #1.083.764.639