On the TV documentary in the UK they went to Baffin Bay where there are Three Graves. They bodies were preserved in Permafrost on X-raying the First body they found that all the sailors organs were in the wrong place. An autopsy had obviously taken place to discover the reasons for his death. Lead Poisoning!

The Franklin Expedition being one of the first to use Tinned Food several companies had tendered to supply the expedition and the lowest quote won the contract. The tins had been sealed with lead solder.

These three bodies are the only clue to missing Franklin and from these clues it seems reasonable to assume as only one of the three Bodies had undergone an autopsy. That they new the cause of his death and as they all were eating the same food from the same tins they new as they sailed from Baffin Bay that the entire crew had also been poisoned and had a death sentance hanging over them.