If McNeish left his #6 on South Georgia, it would be just above the beach, ie, where he and his companions were rescued, and not on the glacier in the interior of the island. ....Arch
According to the Canterbury Museum's article, it was ''jettisoned'' when it ran out of fuel. Wherever that happened I can't guess.
The book I read (some years ago) said they took 2 Primus stoves on the Caird, plus McNeish brought his personal stove. I think they wanted two identical stoves on the boat in case one failed / spare parts. (I can look up the reference, but not tonight.) McNeish was a bit of a prickly character, and not one to be told what to leave behind. He and Shackleton had their differences, but Shackleton needed his carpentry expertise to outfit and help crew the Caird. ....Arch
I think the issue between Sir Earnest and McNeish started when they had to leave the ship, and McNeish's cat had to be killed. They said the hardships would be too great for the cat. I'm not so sure that's a good reason. I'm not a cat person, but it wouldn't have surprised me if rescuers came a year later, and the Crew had perished, but the Cat was fine.