I'd be up for it but not sure how I could get into the gym since I no longer possess a student card and am not a member of the gym...
You only need a student card to get into the team gym itself, even the dressing rooms are non-swipe. So all you have to do is go in with someone else. If you're ever stopped, explain to the staff member that you're there for a team session, and that you're on a year of grace. They'll either understand and let you through, or be too intimidated by the big words to challenge you.