"That may be confidentially. It may be we can progress it without them being implicated."
Mr Tinsley said a $50,000 reward had resulted in a few phone calls and some information being provided. The offer expires on July 1 but may be extended.
The police inquiry, which has relocated from Paeroa to Hamilton, has excluded several suspects but Mr Tinsley confirmed a number of people were still of interest.
Mr Voudouris' family said they were confident the killer would be found.
"No matter how long it takes, Jordan's murder will not be forgotten. Like us, Paeroa is a community in mourning; you will be found and brought to justice."
Mr Voudouris' old restaurant was yesterday adorned with flowers and cards.
His family drove from Auckland to Paeroa to commemorate his passing at a small garden and headstone erected by neighbours and Positive Paeroa.