What's the path_track for?
More detail. You have a trigger_teleport, let's assume its name is teleport_from_here. Suppose you have 3 destinations, represented as 3 different info_teleport_destination. Give each a unique name, let's suppose you call them destination1, destination2 and destination3.
Now, for each of these teleport destinations you need a trigger_changetarget. Give each trigger_changetarget a name (i.e set_destination1, set_destination2 and set_destination3) and a "new target" value of destination1, destination2 and destination3, respectively. Its purpose is to redirect teleport_from_here to a new destination, so all of them have a "target" value of teleport_from_here. Whenever you fire one of these trigger_changetargets, the trigger_teleport will change its destination to the name you set for "new target".
Finally, make a multimanager fire these changetargets individually at different times, effectively making a random choice on which destination it will send you to.
I can make an example map if you want.