"We have carbon monoxide levels that are fatal," he said. "The blood results don't match those levels."
The hospital did not immediately respond Tuesday to a set of emailed questions about the investigation into the three deaths.
Wyoming County Coroner Thomas Kukuchka said he will not rule on the cause or manner of the deaths before he receives complete findings from the state police and is withholding judgment in the meantime.
"Once I get the information to make conclusions, we'll have it," Kukuchka said. "Before I rule on cause and manner of these deaths, someone is going to have to definitively show me that the carbon monoxide caused their deaths."
It appears the three men probably died within hours of arriving at the remote, half-finished mountaintop cabin the chilly evening of Nov. 14, 2006.
They planned to do a little work on the place, and after unpacking some bags, it appears they played chess. They called home that evening to check in, which was the last time anyone heard from them.
As relatives back home became increasingly panicked four days later, Stephen Grasch contacted neighbors in Forkston and asked them to check on his brother and cousins. Those neighbors found the three bodies in the living room area.
State police said the case was never abandoned, had been periodically reviewed and there had even been talk of a reenactment to test for gas levels.
Maureen DiMartino, whose handwritten records document dozens of calls she made to prod investigators over the years, said Tuesday that she was "numb" to learn her son's death was likely an accident all along.
"I know (Tony) wouldn't stop if that would have happened to me," she said. "He would have kept going to find out what happened. So I had him pushing me."
- Rubber chickens, afros and clowns: A look at...
- Why Utahns are some of the biggest spenders,...
- As Ferguson verdict is read, protesters in...
- Immigration reform will boost the economy,...
- Ferguson businesses torched in overnight...
- Ferguson protesters across US peaceful,...
- Review: 4 shopping apps that will save you money
- Attorney General Eric Holder: 'Disappointed'...
- As Ferguson verdict is read, protesters... 68
- Grand jury won't indict Ferguson cop in... 30
- Obama: Americans want 'new car smell'... 29
- Winners and losers under Obama's... 18
- Ferguson businesses torched in... 17
- Under pressure, Hagel steps down as... 15
- Obama immigration plan good, not great... 13
- Obama heads to Chicago to pitch... 12