"Mr Dixon and Mr Gregan hatched a plan to get rid of Mr Goldberg and then to dilute his shares on a trumped-up charge of serious misconduct... when Mr Goldberg exposed Mr Gregan's breach of his endorsement agreement," the letter read.
The script went on to detail Gregan's alleged breach of his ambassadorial duties after he also endorsed the company's "main international competitor" TRX and amended his fee from A$20,000 per year to a salary of A$200,000 along with a car allowance of A$12,500.
Goldberg described the alleged attempt to oust him as a plan to "drop the hammer" on him.
"The manner in which Mr Dixon and Mr Gregan carried out their plan can only be described as cowardly and reprehensible," the letter read.
One reason for this description could be that Goldberg was dismissed on the day before his partner was scheduled to give birth to a baby by caesarean section while he was suffering "severe stress and anxiety".
However, a company source - who wished to remain anonymous - told The Sydney Morning Herald the dismissal process took several months and was delayed at Goldberg's request.
A spokesperson for Gregan and Dixon said they were defending the proceedings.
"As directors and shareholders of [PTP] Fitness Systems, George Gregan and Matthew Dixon have always exercised their powers and duties in the best interests of the company and in accordance with the law and responsible and ethical corporate governance. This will be demonstrated in the pending court cases."
A direction hearing in Australia's Supreme Court is listed for February 10, 2020.
