Thanks for the insight @xj6response, I remember those trails well - I've hiked to most destinations on the island, used to work summers at Camp Latona. Canoed around the island when it was the largest log booming ground in the world. It always impressed me that although the island looked wild, there was signs of human disturbance everywhere - in the middle of what you thought was nowhere you'd come across tools, shoes, shovels, old logging equipment.
We used to raid the core samples when they thought that the copper at Britannia might be found on Gambier, so at one point it was possible that it would become a mine. We broke open the boxes and took the cores as "souvenirs", I guess those sheds are long gone.
As for turning it into a park, didn't Bowen island residents just vote against that?
The people who "own" land on Gambier don't want logging, but they don't want other people on "their" land either.