No I have not codes as of now. Per the workshop manual I was looking at for the 21 model, I believe the ddm only controls the led light for the telescope switch. The other wires go from the switch, to the non serviceable relay at the bjb then back to the mirror connector if I’m reading it correctly.

 

Sounds like the BJB got water in it, there is a recall for that I believe, not sure if it's applicable for you or not. I don't know what else to suggest but here is 2021 wiring diagrams for your truck.