As reported by News.com.au, Mr Bowen cited Mr Hadley's aggressive behaviour as one of the reasons for struggles with his mental health.
The 2GB employees, Andrew Moore and Jesse Perez, spoke to ABC's 7.30 about their experience with Hadley.
Mr Moore admitted he "hated going to work" and Mr Perez likened being called into Hadley's studio to "being fed to the lions".
Both men said station management did not address their complaints about Hadley appropriately and did little to resolve the issues.
Earlier this week, Mr Hadley said he took "responsibility for my former behaviour".
Hadley has friends in high places, regularly inviting Prime Minister Scott Morrison and former Prime Minister Tony Abbott to speak on his programme.