In a claim statement lodged with the Federal Court, the broadcast star said nothing in her $100 million, 10-year contract with radio giant ARN should have led her to be fired just for refusing to work with Sandilands.
On February 20, the pair clashed on KIIS FM's Kyle and Jackie O Show after Sandilands accused his co-host of being "off with the fairies".
But Henderson alleged in court documents she complained to station management multiple times about comments by Sandilands for around six months.
In August 2025, Sandilands made "offensive and degrading comments on-air", she said.
The documents claim Sandilands said some of Henderson's comments were "weird, psychological bullshit" and her belief in "hype words" was negatively impacting her dating life.
Sandilands also referred to her "period time", the documents said.
Henderson claimed she temporarily left the show and spoke to station head Derek Bargwanna and executive producer Natalie Penfold as a result.
A month later, the pair allegedly clashed again and words used by Sandilands were censored by the station.
A day after the argument, Henderson alleged she asked Mr Bargwanna to raise issues about Sandilands' conduct with ARN chairman Hamish McLennan.
The claim document said Henderson was receiving multiple complaints from listeners that Sandilands was perpetrating an "abusive relationship".
Mr Bargwanna told her he raised the issue with ARN management, she said.
When the two clashed for the final time in February, Henderson claimed her employer did nothing to intervene despite being visibly and audibly upset.
She said Sandilands swore at her four separate times in the tirade, as well as questioning her ability to do her job, causing her to be hurt and offended.
Henderson informed ARN she could no longer work with Sandilands on February 26 and that the company had breached its obligation to provide a safe place of work.
She alleged the company did nothing to minimise the risk to her wellbeing despite her repeated warnings.
On March 3, the company's lawyers wrote to Henderson and said her complaint represented a breach of her contract, the documents allege.
However, Henderson claimed the contract did not specify she had to present with Sandilands.
"It was an express term of the agreement that the 'program services' could be provided ... in a live broadcast radio program that did not include Mr Sandilands," the document stated.
For the alleged unfair termination of her agreement, Henderson claims she is owed at least $82.25 million in unpaid fees.
Her and Sandilands both signed contracts worth $100 million over 10 years in October 2023.
Henderson also said she was denied the opportunity to earn a share of station revenue as set out in her contract.
The trouble for the radio giant comes as it fights a separate court battle with the other half of the presenting partnership.Â
Sandilands was sacked by the company for "serious misconduct" during the February 20 clash, a claim the shock jock denies.
He is also seeking the payout of the rest of his $100 million contract.
Henderson and ARN will have their first case management hearing in the Federal Court on April 24.
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