The chief executive of Mater Dei school for disabled children held an internal investigation when a member of staff was accused of grooming a child for sex.

Anthony Fitzgerald, the chief executive and head of the school at Camden, New South Wales, said the NSW ombudsman approved the outcome by the school that the man be counselled, placed under increased supervision but continue in his employment.

He said on Tuesday the man had worked as a social skills educator at Mater Dei for eight years and his behaviour did not meet the threshold for reporting to police.

Fitzgerald is giving evidence at a royal commission inquiry into how the providers of services for disabled children handle sex abuse allegations.

He said he was absolutely sure the current training for staff at Mater Dei ensures they know their child protection policies, procedures and obligations.

“One of the measures of a child safe environment would be in the number of allegations ... that are required to be investigated,” he said.

He has had just two allegations in seven years and one related to concerns about “crossing boundaries and possible grooming behaviour”.

The second allegation had to do with the administration of medications.

Some of the allegations against the worker accused of crossing boundaries were not sustained, the worker was counselled, retrained and Mater Dei made changes to supervision arrangements.

“The action we took was taken in concert with discussions with the ombudsman’s office,” he said.

Fitzgerald said it did not cross his mind to tell police. He also said he would be reluctant to conduct an internal investigation in the future and was concerned that schools did not have the resources to conduct investigations to the standards expected by the ombudsman.

He called for a publicly funded agency overseen by the ombudsman to help small organisations such as Mater Dei to get child sexual abuse allegations investigated – especially when disability was a factor.

He also said that when he took over at Mater Dei he was not told of previous allegations of child sex abuse.

On Monday the commission heard of complaints against the school in the early 90s with one mother saying her 13-year-old daughter was seriously assaulted and the alleged perpetrator, against whom there were several allegations, was allowed to resign and leave Australia.