Find out the following information, if you can:
Did the team just arrive, or were they there when you got there to start your shift?
Do you know how long they've been in the pool so far (if you can tell from context clues/conversation)?
Do you know when they think they're leaving (based on context clues/overheard conversation)? You can find out by asking what kind of team they are and if they have a game tonight when greeting them and making friendly conversation.
If the team sounds like they're going to leave within the next 30-45 minutes, hang tight and make it through your current class and wait for them to leave.
If it sounds like the team is going to be there for a while, or you have waited the 30-45 minutes to see if they will leave and they don't, call the emergency contact number and we will advise; however, it is likely we will cancel the rest of the evening's classes to protect our hotel contract.