Cyprus plane crash - I love a mystery

Reported here, a few curious things:
1. Captain not in cockpit
2. Co-pilot slumped over controls
3. Oxygen masks dangling unused
4. Plane didn't descend upon loss of pressure
5. Interceptor pilots thought they saw a struggle for control of aircraft
6. A lie about a message from the plane (see the couple of paragraphs of the quote below)

In Washington, the executive air safety chairman for the Air Line Pilots Association International told the Associated Press that he found it odd that the crew would not have responded better to a loss of pressure.
"It's a very rare event to even have a pressurization problem, and in general crews are very well trained to deal with it," he said.
Bill Waldock, an aviation safety professor at Embry-Riddle Aeronautical University in Arizona, pointed out that if the aircraft had sustained a severe loss of pressure, the windows should have been frosted over, as they were in the 1999 crash of a Learjet 35 that killed golfer Payne Stewart and four others. The fighter pilots were able to see inside the Helios craft.
Paul Czysz, emeritus professor of aerospace engineering at St. Louis University, said the depressurization theory did not explain why the co-pilot was slumped over.
"Even if the pressurization system was failing, it doesn't fail instantaneously. Even if it goes fast, you can seal the cabin, you've got all the oxygen in the cabin to breathe, you've got the masks, and you've got plenty of time to get to 12,000 feet," he said.
The decompression theory was furthered by a man in northern Greece who on Sunday reported receiving a text message from a passenger that told him, "Farewell, cousin, here we're frozen."
Police yesterday arrested the man, saying they had determined that he was lying.

Very strange indeed.