Generally speaking, I'd not listen to the dealer's service department. I doubt the CLP/SSM is at fault, altho it could be. I suspect they measured current to the siren and assumed that was the same as the CLP/SSM.

The only guy I know is Rick Dunmeyer in Stoystown, PA, four hours from you.

Do you have any local friend who is known for electronics knowledge? Such a person can find the culprit pretty easily, but you won't find such a person wearing a 'mechanic' hat very often.
If you have someone in mind, give them the document I attached below and let them verify what is going on; this is a procedure SPECIFIC to the Crossfire and avoids some of the pitfalls you encounter if you listen to a random YouTube video on "Battery Drain" (not that such videos are bad, it's just that most dont address specific characteristics of the Crossfire).

Let them know they can ask questions here and we can guide them.