If I trigger on the garage door closing, will the wait use the same garage door close to assess the "stays that way for" 5 min or will the Wait only be satisfied if the garage door opens, closes again, and stays closed for 5 min?
I'm pretty sure the latter.
Could maybe try something like this?
Wait for events: All presence departed or elapsed time = 5 min
If all presence departed then
Fan off
Else if garage door closed then
Fan off
End If
You could also try wait for expression, with a duration
Personally, I would re-write the triggers rather than use the wait for event. You could use a sticky trigger for the door closing and a conditional trigger for the presence. Something like this would work:
Trigger
Garage door closed and stays for 5 minutes
or
Presence all depart (only if garage door is closed)
Action
Off: G1 Fan
The two triggers would get around the need for a Wait for Event or Expression as the first action since the triggers match the conditions you want before turning off the fan.