Matt Chisholm had rare and aggressive form of stage IV Lung cancer. He died in his childhood home.
The curse is about a person dying in the act of the search, like digging a tunnel.
Some of the six that died were because of poisonous gas which also lends to the leaving documents in mercury to preserve them theory. High levels of mercury have been corroborated on the island. The levels of mercury should not exist in that area. They corroborated this when they excavated the blue clay pit in the eye of the swamp.
Thanks for the info.