Is by any chance the CLPM wet ?
( It's under the floor panel in the trunk on the passenger side wrapped in gray high density foam, unfortunately you have to remove the rear inside trim panel to get to it. )

I'm thinking maybe the CAN bus which is common to the BCM and CLPM could be compromised by a wet CLPM :
( the PTCM sends an email to the BCM telling it to lower the windows. )