Papprill said confidentiality orders banned her from speaking.
But two sources said she had been subjected to bullying, name-calling and sent emails at odd times.
A former NZ First staff member said: "She felt she was being bullied."
Papprill is understood to have invoked a breakdown-in-relationship clause.
Karen Potter, who worked in the NZ First Albany office, was also barred from speaking about her experience.
But a source said Williams was "heavyhanded" towards her.
"He was concerned about what time she was getting into the office so he got a record of what time the alarm was turned on and off, which made her feel untrusted.
"He was concerned about her making calls nationally - she would get a lot of elderly people from all over the North Island. He got records of that and wanted her to make a record of all the calls she was making and who to and what for."
The final straw came when Williams changed the locks without warning.
"He changed the locks on the office but didn't tell her so she went to work and couldn't get in," the source said.
It's understood both women, who have children, had been badly affected by the bullying.
"It seems unfair that Williams has continued to draw his MP's salary while his victims have been left to suffer," said the source.
Williams did not respond to requests to speak to him yesterday.
Peters was out of the country, and acting party leader Tracey Martin did not respond to calls.
When Williams was mayor of North Shore City, his behaviour was called into question several times.
In 2009, he sent late-night abusive texts to Prime Minister John Key and left an aggressive message on the answering machine of Christchurch mayor Bob Parker complaining about the city's nightlife and "third world" restaurant service.
In 2010, Williams was seen urinating in public after a late night drinking session in Takapuna.
He was not elected in 2010 for the Auckland Super City council, but was returned as a NZ First MP in 2011.
