Darryl Smith flew to Rome this week to participate in survivor meetings timed to coincide with a gathering of the leaders of bishops' conferences from around the world.
Mr Smith had hoped for an audience with Pope Francis and was carrying a letter of introduction with him from the Catholic Bishop of Dunedin, the Most Rev Michael Dooley, who also helped pay for his trip.
However, Dr Murray Heasley, an Auckland-based spokesman for the Network of Survivors of Abuse in Faith-based Institutions and their Supporters, said his visit had already run into trouble.
Dr Heasley, who is also in Rome for the gathering, said in a Facebook post that Mr Smith had been "refused entry into the Vatican to meet with the Pope''.
"We were blocked by the Swiss Guard who dismissed the letter from Bishop Dooley and told us we had to follow a long and time-consuming protocol.
"It was of no importance that a survivor be given priority in survivor week, despite a 40-hour flight from Dunedin.
"They looked at us as if we were crazy, even thinking such a meeting was possible.''
Mr Smith had visited the public square at the front of the Vatican and given interviews to Australian and other international media outlets about his experiences, Dr Heasley said.
Dr Heasley, a former head prefect at St Paul's High School - now part of Kavanagh College - and a University of Otago graduate, has been named as New Zealand's representative on the Ending Clergy Abuse Global (ECAG) group, which is holding five days of meetings and events around the bishops' gathering.
This week's gathering of about 130 bishops, including New Zealand Cardinal John Dew, has been called by Pope Francis to discuss the sexual abuse crisis engulfing the church.