DNA Doe Project volunteer Cairenn Binder said it was the oldest case that they had solved.
She said they weren't sure they'd be able to help as the DNA they initially had was "so degraded".
However, technology allowed the DNA to be built up, which gave them a better sample to work with and eventually led to a match.
The Kiwi connection came from two Kiwis who had uploaded their DNA to the DNA matching website and research tool they used, GEDmatch.
The people turned out to be descendants of Richard and Harriet Vanstone, of Little Creek, Canterbury.
The pivotal connection with the Vanstones was the fact the grandmother of Harriet Vanstone was a Holden. A likely match for an Anne Lehman popped up just minutes later - a sister living in Washington State.
Police then tracked her down and were last month able to confirm her identity.
Binder said she had come across many links to Holdens who lived in Sussex. That same family is connected to an ancestor of Lehman, who is also from Sussex.
Today the Josephine County Sheriff's Office (JCSO) announced that the DNA Doe Project has successfully identified Annie...
Posted by DNA Doe Project on Thursday, 14 March 2019
"Without knowing the Holden name we wouldn't have been able to solve the case, so it was necessary for us to do research on those people from New Zealand because their DNA gave us that clue about that piece of DNA from the Holdens."
Prior to that they initially found up to 60 matches and several common ancestors, most of whom were in New Zealand, Australia or the United Kingdom.
"That was kind of a red flag to us when we saw the Sussex Holdens because we had seen a lot of our matches that we had built out had family members in Sussex, it seemed like a hot spot and, as it turned out, that Holden family was connected to Annie's identity."
She said one red-herring of their investigation came from the bra that Lehman was wearing. It was made by a company, Loveable, who were in New Zealand. However, they later discovered the bra was also made by a company of the same name in the United States.
There was also a piece of jewellery, a ring with the initials AL engraved on it, but Binder said they couldn't take that as any confirmed lead initially.
"That could have been carved there for any reason, it didn't have to be her initials.
"After we found her real name we were really excited about the ring but at the time we didn't know."
Binder said being able to confirm Lehman's identity was not only exciting to determine who she was, but also help police determine how she died.
"The thing that's exciting about it, is that it's highly suspected that Anne Lehman was murdered and without the identity of the victim there's nothing that police can usually do to help capture the killer. But now that they have her name ... they can finally track down her killer after all this time."
Sheriff Dave Daniel of the Josephine Country Sheriff's Office in Oregon confirmed the cause of her death was still under investigation.
He paid thanks to the DNA Doe Project team for their "painstaking" work in analysing DNA from Jane and John Does.
"Without the DNA Doe Project orchestrating the effort to bring Annie Marie Lehman home, it may well have taken another 47 years before Annie would be identified and reunited with her family."
Today, Josephine County Sheriff Daniel put out a press release regarding a positive identification on a 48-year-old cold...
Posted by Oregon State Police on Thursday, 14 March 2019
Helen Vanstone, of North Canterbury, said they had seen Richard and Harriet Vanstone's names mentioned in a historic book on the Banks Peninsula.
Since the link with the cold case, they'd dug deeper and discovered that Richard and Harriet Vanstone were the great grandparents of her husband, Murray.
She said they first became aware of the case last year but did not realise they had managed to confirm her identity until Tuesday night.
She said it wasn't their DNA that was used to help solve the case but likely one of the other descendants of the family which was "huge".
