Power divider input shaft broke? Driveshaft turns, truck does NOT move

My driver took my truck today to drive a 96,000 lbs gross load. He reported, coming off a stop, a scrunching noise and the truck would not move. He thought it was the clutch. I did some diagnostics when I arrived. The clutch is fine. The driveshaft turns, but the truck does NOT move. Also the power divider differential lock does NOT help.

Here's the video:

We brought the truck on my RGN trailer and the other tractor.

So, my thoughts are racing. And I think that it could be the power divider input shaft driven by the drive shaft? Any other experiences?

 

It could not be the axle shaft, because the truck does not move with interaxle differential engaged.

 

The truck was dragged very easily without any untoward noises or vibrations, though the engine was running. There are no noises at all when I put the truck in gear running and then look and touch the power divider (the truck does not mover as I said). Also absolutely no noises when clutch is engaged/disengaged, though I do feel the shafts starting or stopping to turn. Engaging and unengaging power divider lock does not seem to produce any noises also.

 

Good question. I did use it to get out of a small hole recently. THis much I remember.

 

Here are the pictures of the power divider and then the picture of same partly disassembled, with broken parts laying separately on the left!

Looking at all this, I am puzzled. The power divider shaft is a solid through shaft, splined on the far end, and it should be directly driving the rear axle, through said splines? Am I missing anything?