Best thing to do is set up a dummy account then that protects your own MDE and anything on it. Link everybody up (if you do not want to do this then that’s ok everyone can use Photopass cards but may not get ride photos and deffo no videos). Remember to link your own personal MDE to it also. To stop all reservation etc info going on just ensure that everybody’s settings are set to view only shared activities only. Also ensure add to family list and this person can view and purchase my photos are ticked. There is no order that people have to go just make sure that the person who goes first will still get their photos by the time the last person comes back ( photos disappear from day 45 which is why most people just use a 30 days window to allow editing and downloading befor pics start disappearing). You decide how much control is given but would advise strongly that nobody downloads anything until everybody has returned and edited then you do a download all and then everybody downloads from the my downloads section in parts. It is up to you when you give out the email and password to the dummy MDE. If you are not the first participant you may want to wait until just before you go or just before the first participant goes. Just ensure that people have the info in sufficient time to enable editing but with a strict no downloading policy.