RTE veteran Mike Murphy has described the station's defamation of Fr Kevin Reynolds as "shameful".
At the same time as two of the broadcaster's senior people temporarily "stepped aside" over the controversy, several big names have condemned the libel.
News At One presenter Sean O'Rourke described it as a "terrible error", while John Bowman said it was the "largest error that's ever been made in RTE".
The comments came as Ed Mulhall, managing director of RTE news and current affairs, and Ken O'Shea, editor of current affairs, left their normal roles in order to facilitate inquiries into the Prime Time Investigates: Mission To Prey programme.
Mr Mulhall was given a round of applause when he addressed the RTE newsroom last night to apologise for the hurt and pain endured by staff in recent days.
Both men will remain on full pay while the Broadcasting Authority of Ireland carries out an investigation. Reporter Aoife Kavanagh and executive producer Brian Pairceir are also to be removed from on-air programmes for the time being.
The controversy overshawdowed the launch of John Bowman's book, Window And Mirror: RTE television: 1961 -- 2011, at the National Museum last night.
Arriving for the event that was part of RTE's 50th anniversary celebrations, Mike Murphy said it was the right choice for the executives to step aside.
"I think it's shameful... I feel very sorry for him, and if you want to dish it out as journalists do, then you have to step away (when something goes wrong)."
Sean O'Rourke said that it was a "very difficult" time for everyone in RTE because "a terrible error was made and we're just hoping that when it's all over that the station will be able to regain the trust of the Irish people."