Looking for help, advice or thoughts.

I purchased a 2011 T&C Limited last November. The dealer where I purchased it brought it in from another dealer in another city.
Early this spring the console display said the rear park assist system needed to be looked at as well as the side mirror light. I didn't end up taking it in until the beginning of July. I took it to a local dealer (van was not purchased there).

They repaired the side mirror but called and said they looked at the park assist system and did not want to touch it because there was a tow hitch but it was since removed and there was a wiring issue. They recommended I take the vehicle to the place of purchase.
I left the issue until this fall and then ended up booking it into the place of purchase in another city. The service rep called and said two of the park assist trim rings were missing and those particular sensors were the damaged ones. The service rep also stated these do not fall out, they would have to be removed. Further to that, he informed me that it would not be covered under warranty. I also had to understandably pay them a fee to look at the issue.

I called Chrysler's customer number and emailed them as well. The telephone rep and email reply both stated that they would not cover the cost of the replacement rings or labour. They also stated it was up to me to find out what dealer removed them and work out the solution with that dealer.

The only thing I can surmise is the dealer where the van was at originally (where my dealer found and purchased van from) messed with the hitch/park asst system, my dealer did, or the local dealer that looked at the issue first in the summer did. Pretty hard to figure that out.

So my questions are:
*The windows sticker states I have the $700 trailer tow prep group. Upon purchase, I did not see a hitch and assumed it was just wiring that came with the package. The first dealer to look at the issue stated a hitch was removed with wiring issue. Is this correct? No actual hitch with the tow group package?

*If a dealer removed a hitch, would this entail messing with the park assist trim rings?

*Would any dealer have a reason to remove or mess with this stuff?

*Any other ideas or suggestions as to what could be going on here?

I feel Chrysler should cover this or at least help me in solving the issue. Again, there stance is that I'm on my own with this.

Thanks in advance.