Hi KateG. thank you for your reply. It's quite hard for me to be very sure as many people can access the terminal via logmein and some are a couple of time zones away.
The main reason I surmise the terminal has been inactive despite showing "in session" is that I kept checking by killing logmein and restarting it and it kept showing in session but then when I finally login the main app that people use and has a timed auto logoff is not signed in. It's just impractical to email a whole bunch of people to ask if they are on.
Logmein does show "online since" but that seems to reflect when the machine was last rebooted. I just wish it showed when was last activity.