The group - representing more than 25,000 survivors and supporters internationally - aimed to support those abused in all faith-based settings.
Dr Longhurst told ODT Insight that would include survivors in Otago and Southland, and he had already discussed the name change issue with the Roman Catholic Bishop of Dunedin, the Most Rev Michael Dooley.
Change was needed and the focus should be on the symbolic meaning behind such a move, which would be "immensely healing" for survivors, he said.
However, opinions differed among some Dunedin-based survivors.
One, Michael Chamberlain, said a name change would support those targeted by a cluster of paedophiles operating within the diocese during Bishop John Kavanagh's time.
That included the former priest and convicted paedophile Magnus Murray - jailed in 2003 and defrocked earlier this year - but also other offenders, he said.
Bishop Dooley's decision to call in the National Office of Professional Standards (NOPS) instead was "quite incredible", Mr Chamberlain said.
"What we have got is the church investigating the church," he said.
Dr Murray Heasley, a spokesman for the Network for Survivors of Abuse in Faith-based Institutions, agreed.
He believed NOPS had been called in at the insistence of the New Zealand Catholic Bishops Conference, which was "well aware" many witnesses were dead or remained reluctant to speak.
Asking survivors to relive their trauma again was "morally and ethically reprehensible", he said.
However, another Dunedin survivor - who cannot be named for legal reasons - argued against a name-change, saying it would be expensive for parents.
The school and its staff were not to blame for events at St Paul's High School, and the name should remain, he said.
"Nothing happened in 30 years of Kavanagh College," he said.