Hi Jeremiah,
Was this organist at Napier or Wellington? There's a 4 hour drive between the two places.
And do you have a name for the student or is it possibly one of many?
I don't know of any catters in Wellington but I suggest you contact the NZ Symphony Orchestra and ask the person in charge of all their music.
I don't think the NZBC would be much help - Broadcasting House has been pulled down and turned into a parking lot, TVNZ was cast loose and is currently trying to sell it's complex at Avalon (which was the dream for the future when I worked for them - 30+ years ago) and now you have to search around to find all the little radio stations, all in different hiding places. There's not even a decent sized recording studio available.
The other possibility might be a letter to the Wellington paper - The Dominion Post at dompost.co.nz or at PO Box 1297 Wellington.
Robyn