The marine had an interesting idea. One he had no qualms about doing.
So Zuriel walked off and disappeared around the doorway he entered from and went out from sight from the others.

There he searched for an cogitator system access and workstation, which was reasonably close by. Walked over to it and began to work its systems.
A pair of crewmen walked by, giving the lurid techpriest some odd looks but then thought nothing more of it. After all, regular crew don't usually keep track of the techies, and the techies could very well change appearance and bionics between each time they saw them for all they know. On top of that they are performing weird ritual with their oh so sacred technology that the crew mostly had little idea of how it works.
So they had no idea that Zuriel was rerouting control to a new user he was establishing, hidden of course, which could easily override the main controls of the sections Lucius mentioned. At least temporary, temporary being probably an hour or so at least. System security being something that was usually woefully under specifications and seldom of any real quality unless actively attacked or on a system with high importance like a navy capitol ship or important hive cluster or something in the arsenal of the adeptus mechanicus.
This being barely an escort vessel, with few personnel who would be even aware such a system existed and the modifications being made from within the correct mechanicum parameters. This one would be hard to spot.

He prepared a simple activation word, titanhammer, which would switch door controls to him when he called for it.

[hider=Timeframe]
Zuriel went away and will be doing this for a while. He can't affect the events in the armoury now.
[/hider]