Wow....tough day!
In my opinion and it is only that....although it would have been nice if the dealer service personnel had told you that it was not secured for travel... it is ultimately up to us as owners to make sure the rig is set to roll. Like when I fly....you might have buckled your own safety harness, but as the pilot in command it was up to me to check it for your safety.
I would think the dealer would at least help you to get another at cost anyways?!
Sorry to hear of your troubles! Man, I am glad I don't have to be in your shoes today! God Bless.