The police said it appeared to be a case of suspected suicide.
The owner of Dryden Lodge, Ron Lapread, said he had no information about today's death.
"I was just called and asked to come by the lodge. I'm sure the people at the lodge are really shook up."
The bodies of Ellwood and Hamilton were discovered by a maintenance worker in March.
The police, who said at the time they were not looking for anyone else in relation to the matter, conducted an investigation for the coroner.
A source told the Herald Hamilton had "quite a few convictions".
In 2007, he was convicted of rape in the Waitakere District Court and sentenced to five years in prison.
There is no suggestion his previous offending is connected to what happened at Dryden Lodge.
He was the son of Kiwi soul singer Josie Rika. Ellwood had been a fashion and beauty editor.
WHERE TO GET HELP:
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.
OR IF YOU NEED TO TALK TO SOMEONE ELSE:
• LIFELINE: 0800 543 354 (available 24/7)
• SUICIDE CRISIS HELPLINE: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• YOUTHLINE: 0800 376 633
• NEED TO TALK? Free call or text 1737 (available 24/7)
• KIDSLINE: 0800 543 754 (available 24/7)
• WHATSUP: 0800 942 8787 (1pm to 11pm)
• DEPRESSION HELPLINE: 0800 111 757