Call and change the reservations in your name. Then u show your id and all is good
If he bought the tickets, then yes. If not, I think he'll be fine.
You can but if the tickets are in his name or he wants alcohol then it becomes and issue. But really only for booze and pre-purchase tickets as far as I know. I've only been once recently.
Tough one. Not certain. Best to call the venue on this one.
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