Earlier quoted context omitted.
The co-pilot was breathing normally for ten minutes while the door was being hammered repeatedly. Interpreting this as 'deliberate' inaction is hardly 'stray speculation'.
Isn't that a little bit off he didn't mutter any words after seizing the opportunity of his co-worker's unplanned leaving of the cockpit ?
I would not be surprised to learn in the coming days that he did say things. But I don't think we'll find out until the investigators have a solid grasp of what this means for the investigation.