...for the record, DM didn't necessarily give a precise position for Ens LaRue, either.
From her boarding post timestamp and location (Main Shuttlebay) I've been under the assumption that the encounter between LaRue and Briggs has been tacking place on Deck 4... Didn't note in the post that LaRue boarded a lift or anything, so, Briggs and LaRue are likely somewhere close to the Main Shuttlebay.
If it helps either of you at all, play it as Briggs got notification of his new Security officer coming aboard and went to Deck 4 to "find her" and help get her pointed in the right direction.
Note: Ops (or any other dept, for that matter) can be contacted via your combadge and/or accessing the computer... No need to go to the actual office.