Peter Beardsley's accusers have refused offers of mediation to resolve Newcastle’s academy crisis.
Newcastle are investigating the Under-23 boss amid claims from a number of his players of bullying and racism.
Beardsley “categorically denies” the allegations.
The club are due to hold a grievance meeting at 2pm on Thursday with winger Yasin Ben El-Mhanni, whose official complaint of a campaign by the Magpies legend to humiliate him was revealed by Mirror Sport last week.
It is understood the 22-year-old – who raised concerns in November – and his representatives were offered a meeting with Beardsley and a mediator to try to resolve the issue. But the player, born in England to Moroccan parents, declined as he felt it would not go far enough.
Others are believed to have similar concerns and also rejected talks, with many worried about their long-term futures if they go on the record.
About 14 players will be spoken to by the club’s human resources team, chief executive Lee Charnley and safeguarding boss Steve Swinyard.
Written statements will be re-examined.
Beardsley’s hearing was on Monday in the presence of Charnley, Swinyard and a PFA representative.
The 56-year-old is said to be fighting to save his job.
He arrived to take training on Tuesday but left when advised by club lawyers not to have contact with players who made statements with allegations against him.