2008 Hummer H3 Run Perfect Cold, but Stalling at Warm Idle

I have a 2008 Hummer H3 is now “Stalling” after having the Cylinder Head Repaired. The job included a new Timing, crank sensor, cam sensor, MAF, MAP, and VVT Oil Control Solenoid. On a Cold Start Up, the vehicle runs perfect with no stalling issues. After “Warm Up” as the Electronic Throttle Closes, the vehicle stalls in any gear (including Park or Neutral. On a warm engine, if I use the accelerator to control the idle speed at 900 RPM, the H3 will not stall. I have code 0017 (cam / crank correlation).

I have reopened the engine to look at the timing and the timing marks appear to be correct. I think all is ok there.

I am slightly concerned about the exhaust cam phaser. I don’t know much about phasers. When at rest with the engine off, the cam sprockets are perfectly timed, but the exhaust cam flat is not horizontal to the head, therefore the exhaust phaser is not either. The exhaust cam flat and the exhaust phaser are connected and facing maybe 11:00 instead of horizontal to the head at 12:00. I can rotate the exhaust cam phaser with my hand maybe 1”+ clockwise to get it to face 12:00.

I need to give an example of what my engine is doing.
*Let’s assume then the engine is off and #1 is TDC.
*At that point, the flat on the rear of the intake camshaft is horizontal to the head.
*The flat and the phaser on the exhaust camshaft are connected on opposite ends of the exhaust camshaft and facing 11:00, not 12:00.
*At rest with engine off, should the exhaust camshaft phaser be in a fully advanced state (meaning facing 12:00) OR is a slight tilt to the left, facing 11:00 ok?
*My exhaust phaser is facing 11:00 at rest
*Does that mean that my phaser is bad and needs to be replaced?

I have seen many posts on different forums with the exact same issues, but I have yet to see a diagnosis. Thanks for taking the time to read and potentially help!

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If you can move the camshaft phaser by hand, the locking pin is no good and the phaser must be replaced.

I rotated the phaser clockwise by hand, then I tried to rotate it back counterclockwise, but it wouldnt budge. Is the pin supposed to lock in at the 12:00 position, are there multiple pins in the phaser, or was it the camshaft itself that had the phaser bound up?