King is currently in a lot of pain at North Shore Hospital with a broken collarbone. She might be kept there overnight for observation.
Buswell had bought the tickets months ago and King had planned a special trip to Auckland for the concert. Buswell said her mum had been "over the moon" to be going.
"I thought we'd just pump her up with painkillers and she'll be right but she hasn't actually moved since she got hit so that's not going to happen.
"She's very disappointed ... it's a once-in-a-lifetime opportunity."
Buswell said the incident was a "freak accident". The kite surfer had offered to reimburse them for the $300 ticket.
"The man who hit her was really devastated as well. It was traumatic for him too.
"He's been really nice, he offered to reimburse [for] the ticket. I thought that was really kind of him.
"We offered the ticket to him but he's already going."
Buswell is not going to relinquish her ticket though.
"I'm like, 'Mum I'm still going', my husband will look after her."