When I went on opening weekend, there was definitely a box office and a phone number. There were some modular offfices/trailers right after the parking lot and before the main venue entrance.
You might be able to buy tickets from the box office the night of a show, but since the venue is owned by Live Nation you'll still be paying their outrageous service and facilities fees.
Honestly im not to sure had tickets pre ordered. I did see a will call box office so there's probably one and not to sure about the number. Hope this helps
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