Just a thought
Im by no means an expert but I do have some mechanical sense. It sounds like maybe a faulty switch if they didnt replace it. There could be a loose wire a short or this switch itself is crap. I have a friend with a 2011 dually and and his wouldnt shift out of 4x4 when he engaged it. Electronics are a pain in the butt and they just keep adding more to our vehicles. I have a 2011 and I would have rather had a manual transfer case shifter but its no longer an option. If you had a Ford wiring problems would have showed up if they hadnt already. It sucks that you switched to Dodge and had a problem but hopefully you dont have any more when you fix this one.
Im by no means an expert but I do have some mechanical sense. It sounds like maybe a faulty switch if they didnt replace it. There could be a loose wire a short or this switch itself is crap. I have a friend with a 2011 dually and and his wouldnt shift out of 4x4 when he engaged it. Electronics are a pain in the butt and they just keep adding more to our vehicles. I have a 2011 and I would have rather had a manual transfer case shifter but its no longer an option. If you had a Ford wiring problems would have showed up if they hadnt already. It sucks that you switched to Dodge and had a problem but hopefully you dont have any more when you fix this one.