Worf was a Lt. J.G. and was promoted to lieutenant when he took over security.Jack Samuels is a Lt. J.G., so he wouldn't be a department director.
Aboard a US Navy ship, like an aircraft carrier, I read this:Key Ranks & Roles on the Enterprise:Lieutenant Junior Grade (2364–2365): Began as a relief flight control and tactical officer.Lieutenant (2366–2371): Promoted and served as the chief security/tactical officer.Lieutenant Commander (2371): Achieved this rank just prior to the destruction of the Enterprise-D in Generations.
I figure, on a vessel of about 300+ crew, you are right, but there is enough flexibility and the newness of the community as a whole, means only the very top brass onboard would know the truth. T'Nilz did not expect to be trapped permanently onboard, and was just trying to move freely through the ship to a more permanent hiding place.A US Navy aircraft carrier generally has a small number of personnel holding the specific rank of Commander (O-5) in top leadership positions, but many more within the broader ship and air wing structure. While the Commanding Officer (CO) and Executive Officer (XO) are typically Captains (O-6), key department heads, such as the Chief Engineer or Air Boss, are often Commanders, along with several squadron COs in the air wing.
I didn't envision T'Nilz as a spy or infiltrator like that. More a Marine Force Recon type. Splinter Cell special forces ghost operative; alone or as a team, to observe and report, maybe disrupt and disable, not act the secret agent type. She just got caught by the events of a maiden launch in the wrong place at the wrong time. Her expertise is definitely not disguise and "fitting in". She's more an adapt and improvise.
The choice of rank "commander" was only expected to get her to a cabin. She, as you can see, has discipline, but it slips, at times.
Making her "acting head" of security would be fun, but a dangerous game on the part of the Doohan's leadership. How would they limit her access?
I figure Commander Bet, with her embassy and diplomatic experience, and Captain Williams' combat-as-a-last-resort attitude, they may try to "turn" their stowaway; or at least come to some sort of temporary alliance.
-Will