Half of charities fear public trust in their work has been permanently damaged by the top-ups and pay-offs scandal at the Central Remedial Clinic (CRC).
Amid continued calls for former chief executive Paul Kiely to repay some of his 742,000 euro pension, The Wheel, which represents Irish charities, said 97% believe their reputations have been shattered by the controversy.
The alarming trend was revealed as Maria Nolan, the mother of 17-month-old Oisin who uses the CRC four days a week, cried on national radio in disgust at what hard-fought donations were being used for.
And Health Service Executive chief executive Tony O'Brien said money Mr Kiely secured for his retirement could have shortened waiting times for CRC clients.
The agency is taking legal advice on the pay-off.
In response to the fall-out the Government said it is committed to appointing a charity regulator this year but Deirdre Garvey, chief executive of The Wheel, called for a d etailed timeline on the new role.
"A crisis of public confidence has engulfed the charity sector since the revelations about the failures at the Central Remedial Clinic," she said.
"While we know that the Charities Regulatory Authority will not be a panacea against governance failures and malpractice in charities, all stakeholders agree that it will set clear requirements in relation to governance practice, activity and financial reporting, and increase transparency and accountability.
"In doing so it will provide the public with the necessary assurances to maintain public giving."
Before Christmas, Fundraising Ireland said charity donations had plunged 40% in the wake of the top-ups controversy and also warned about phonecalls coming in on an hourly basis of people cancelling donations.
The CRC scandal was disclosed at the Public Accounts Committee which yesterday heard Mr Kiely walked away with a gold-plated pay-off worth 742,000 euro.
He previously only admitted a pension pot of 200,000 euro.
The money was secured from donations and paid out of accounts held by the Friends and Supporters of the CRC.
An audit by the HSE has uncovered Mr Kiely's pay-off included 200,000 euro tax free, 273,336 euro which was taxable and 268,689 euro paid to Mercer's consultants to top up his pension fund as though he had worked until November 2016.
John McGuinness, PAC chairman, suggested a fraud squad investigation might be needed over the affair, with the Office of the Director of Corporate Enforcement and gardai being called in.
Brian Conlan, who took over from Mr Kiely as head of the CRC but lasted only four months in the job, denied all knowledge of Mr Kiely's pension.
Parents of children who use the CRC's valuable services have appealed for people to continue donating.
The Wheel said a survey of 150 of 930 members found that 97% believe that the CRC affair has damaged public trust in charities, and 54% believe that it may be permanent.
One fifth reported that donations are already down by more than 10%.