Would it still be called pilot error in case of pilot sabotage? The Air Current article only mentioned the movement of the fuel control switches being at the center of the investigation, leaving a possibility that they could have been reset. The WSJ piece (with their own sources) goes further and claims that the switches were turned off, leading to the loss of thrust.
If the preliminary report isn't going to be made public, there's a good chance of more leaks to the media.
If the Fuel control switches caused the loss of thrust, they would have a difficult time passing that off as Pilot Error.
Those switches are only used to start the engines and to stop them. It's not something one could do accidentally. That would be like removing your car keys from the ignition and thowng them out the window while you're driving.