Calling the venue seems like a good idea. Just google it and call them
Usually you print the tickets. Did you get an email perhaps with a link to print??
Call Meadow Brook I am sure they have the tickets, there should be a number on they letter
Contact the venue!
Also, did they order through the venue directly? If they went through ticketmaster, or a website have them follow up there. Usually they do email it and you can either print the tickets or pull them up on your phone
Your best bet is to call the venue and ask.
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