I would image the dealer has all the service records on file for that truck, so you should be able to draw a conclusion from that.
Welcome to the forum!
I think you'll find most shop that "alter" parts will not really advertise that, or even want that activity referenced with their name.
But, good idea that can be used for sure.
Welcome! Like mentioned, it sounds like the ECM connections isn't seated correctly. I would unplug it again and be sure nothing is bent up and everything lines up properly.
Otherwise, it could be a faulty ECM/Tune. It's possible!
Hey @Althecraneguy ! Sometimes the software can't even resize the picture if it's to big... but yea, going to any website or using the picture editor of your choice (Windows --> right click, edit, then resize) works for me.