I'm with people who think that command guy is just a middle man.
C'mon it's not like fleet admiral contact with every fighter squad on a regular basis, every mission, day by day.
I think pretty much everyone here agrees he's just a middle man, but for whom? The three options I see are fighter operations for Aquataine, command for 3rd Fleet of which Aquataine is the flagship or last but not least the very central command of the GTVA. My personal opinion is that since he's representing someone who can move a lot of ships, including (if my memory serves) warships from other formations such as Vesudan vessels from the 13th Battlegroup, he represents the very central command. This may seem strange, but to be honest, how many battles can be raging at the same time? A dozen? Two dozen? For central command with FTL capabilities, who likely employ hundreds if not thousands of people, it would be easy to keep tabs on each and every combat area at any given time. That's my personal opinion of course.
As for the original question. If the man really represents a central command, he and his superiors are likely far behind the lines, maybe in Delta Seprentis or Beta Aquilea. If he's just a fighter ops operator on Aquataine he also survived as Petrarch (who commands Aquataine) is narrating the final cinematic, which means he and his ship (and any operators on that ship) has survived. If the man represents the command of the 3rd fleet as a whole, then my assumption would be that he was on Aquataine, as the destroyer is supposed to be the flagship of that fleet. Overall the chances he and whoever he represents did not survive are low.