Hey there, the only known bug was Drone 1, which was inaccessible to people who didn't own Beyond Light. You are still missing Drone #43, which is under the staircase leading down to the microwave trap room in Operation: Seraph's Shield. It is so commonly missed, that I guessed it was this one before I looked at your triumphs. Because it is before Drone #42 (in the secure Operator room after the microwave trap room), despite being a linear location, [u]many guides will label these two the other way around[/u]. Which is fine when you follow the full guide but causes issues when people are trying to fill gaps in the triumph. So, check the spot that guides say is #42, this is #43 on the triumph.