"The council wanted us to move it. We wouldn't, because if we moved it to a backwater they might have said out of sight out of mind, it can just rot there. So we told them it was only insured while it was tied up to the wharf and if we move it, it's your responsibility."
Asked whether he suspected that someone might have deliberately interfered with the vessel, he said: "I don't think anyone I've been talking to would be so stupid or so evil to do that, but it's strange, and it's worth investigating."
"On the balance of probability, it's probably just natural causes," he said.
"The alarm worked reasonably well when we didn't need it, then when we did need it, it didn't work. I don't have a conspiracy theory."
Society treasurer Hugh Gladwell said he had asked police to look at footage from "a number of webcams" in the area.
A spokesman for Panuku Development Auckland (formerly Waterfront Auckland) said Panuku had asked Ports of Auckland Ltd to supply any film footage it had of Wynyard Wharf.
Mr Alston said the vessel's insurers were also trying to find out what caused the sinking because they faced "a six-figure job" to remove the wreckage.