Reports suggest there was a violent incident that occured in the early hours of the morning, but Napa's involvement is still unknown.
A neighbour claimed there were noises of breaking bottles and screaming before the authorities arrived.
“This morning (Sunday) about 3am I heard a woman shouting at someone but I could not hear any voices shouting back then the next thing I heard was screaming and bottles breaking,” the neighbour told The Daily Telegraph.
Over 600 people attended the exclusive event held at Theo Chamber's - son of Chambers cellars founder Steven Chambers - luxurious Palm Beach mansion.
Mr Chambers noted the incident took place after the party had finished.
“There is no information suggesting that the charity event and [incident] were in any way connected,” he said.
All three of the injured have since been released from hospital.