Tauwhare, from Hokitika, was discovered dead at the Lextan tanning studio in South Wales on Saturday.
Booked in for an 11-minute appointment, the 30-year-old was reportedly in her designated room for more than two hours before her body was found after her mother-in-law came searching.
It is understood the cause of death was sudden arrhythmic death syndrome - when someone dies suddenly and unexpectedly from a cardiac arrest.
Husband Ifan Jones (23) believes salon staff were negligent and forgot that Tauwhare was in the building until the alarm was raised.
"How can that happen," Jones tells The New Zealand Herald.
"The room where she was is literally bang in front of the reception desk, you cannot miss it."
While he accepts it might not have saved her life, Jones said his wife could still be alive if staff had checked on her after the 11 minutes were up.
The Herald contacted the tanning studio company for a response to Jones' allegations.
A Lextan spokesperson confirmed a customer had died at the Fforestfach salon and said it was assisting a police investigation.
"We give our condolences to the deceased's family and friends, and we have also offered counselling to any affected staff.
"We are co-operating with the investigation into this case by South Wales Police and any further inquiries should be made to them at this time."
South Wales Police Detective Inspector Gareth Jones confirmed to the Herald police were called around 4pm on May 28 after reports the body of a woman had been found at commercial premises.
"Emergency services attended and found the body of a woman in her 30s. There are believed to be no suspicious circumstances surrounding her death. Her next of kin have been informed and a file has been passed to the coroner."
Tauwhare, employed by mental health wellbeing service VitaMinds, finished work at 1pm on May 28 ahead of her booked session at the tanning salon for 1.45pm.
Jones, a warehouse worker, had been texting Tauwhare throughout the day when she stopped responding.
As they regularly texted, Jones found her silence odd and proceeded to call her multiple times to no avail.
Knowing something was wrong, he called his mother to check their house and then the salon.
Salon staff initially showed Jones' mother to an empty room. Presuming Tauwhare had left, Jones' mother exited the salon, only to be called back in by staff who had found Tauwhare's room.
The door was locked, but looking underneath, Jones' mother could see Tauwhare's legs on the ground, having collapsed on the floor.
Jones said by that time, it had been more than two hours since Tauwhare's appointment began.
Arriving at the salon a short time later, Jones said one staffer appeared to be "panicked" and "frantic".
He suspected a miscommunication during a staff changeover had meant staff were unaware Tauwhare hadn't exited her room.
He acknowledged his wife's life may not have been saved even if staff had checked on her, but said it could have increased her chances of survival.
"Even if they were able to help within the first 5-10 minutes, I'm not saying they would have saved her life, but there's a chance."
Jones didn't know whether Tauwhare had any heart conditions that might have contributed to her death.
He said losing his wife had been incredibly tough for him, friends and family.
"I'm a mess, I'm just depressed and I don't know what to do with myself."
He referenced how much love and support he was being shown by Tauwhare's family and friends.
Tauwhare's family were understandably devastated, Jones said. Some friends had posted loving tributes on social media.
Tauwhare and Jones had met on a night out in Bristol, England two years ago, while the Kiwi was travelling.
"She was amazing, I've never [met] anyone like that before," he said.
The pair married on September 1, last year. It was a small wedding, held in Swansea and witnessed only by his parents.
Tauwhare's trip to the tanning salon had been in preparation for a holiday to the Spanish island, Tennerife.
Having spent about three years away from New Zealand, Jones said they also planned to travel here in December - where he would have met his wife's family in person for the first time.
"She was so excited. I was as well, but I was so nervous," Jones said of meeting the family.
Tauwhare would often call home over FaceTime and had a strong group of friends around her.
Jones described her as a very generous person and extremely proud of her Kiwi roots.
However, Jones felt Tauwhare's memory was not being honoured by the salon where she died.
He said he hadn't had any contact from Lextan and staff were seen smoking outside the shop in the spot his mother was laying flowers.
"They haven't said nothing to me, they haven't sent condolences, they were open the next day, what does that say?"
Jones was now planning on bringing Tauwhare back to New Zealand. A GoFundMe page, started on behalf of Jones, had raised almost $12,000 to help travel costs.
In a WalesOnline article, Detective Inspector Gareth Jones of South Wales Police believed there were "no suspicious circumstances" surrounding Tauwhare's death, which had been passed on to the Coroner.
Jones understood a police investigation was ongoing but said he wouldn't stop until the truth was known.
"Even if the police say there isn't [an investigation], I'm taking it all the way.
"I'm pretty confident I'll get justice."
