The laywers are coming...

Can anyone provide information to help me with with the following:

A builder in a mountain region of the Northeast insulated a homes’ cathedral ceilings in the following way. From the inside of the house he installed 1" foamboard up against the underside of the roof sheathing. Then he installed the duravent foam baffle (that helps maintain the gap for airflow) under (and up against) the foamboard. He then installed fiberglass insulation with kraftface and then the drywall. Isn’t this a dbl vapor barrier? Why would he do this? Is this common??? I think i was successful in attaching a photo that might help you understand what i’m describing.

I dont understand why he would put the foam AGAINST the sheeting, Kinda defeats the purpose of venting all together. Unsure about the double vapor barrier.

Post script, I have seen Celetex air gaped away from the sheeting, creating a vent.