Need help with a 2015 Durango R/T that starts but won’t idle and dies. Everything works except it starting..

 

If the IAC valve has not been changed , I would look there first.
next fuel delivery

 

Have you checked for any pending or stored diagnostic codes? If you open up the throttle once it starts can you keep it running? And if so, does it run very roughly? Have you inspected the intake air tubing to make sure it's all properly connected and there are no large air leaks? I don't recall if that engine uses a MAF Sensor or a MAP sensor, but if a MAF sensor, any air introduced after the sensor can cause the symptoms you describe. If you unplug the MAF and it idles better (albeit still roughly) that would be another indication that you have a large air leak in the intake system somewhere.

-Rod