Hi JDH. I understand your frustration. And unfortunately, although we are all trying to help, this thread took on a bit of mission creep and got off track a bit.
I would only add that we often hear "The Service Manager (or someone at a Dealership) told me he sees (fill in the blank) quite often". It seems service personnel have a habit of saying things like that. Perhaps to get the heat and bullseye/anger off themselves? Just theorizing.
However, I can honestly say that yours is the first case of this type of door damage that I have seen or heard of on all any/all of the Lincoln/Ford forums I am a member of.
Of course, I also understand that is of little comfort to you.
Concerning the corrosion on the trunk lid: The Corrosion/Rust thorough Warranty is 5 years/Unlimited mileage. So we go back to what the "In-service date" is for your Continental (oh no...lol).
And I can say that this problem is one I have seen a few cases of, and the owners have been able to have it corrected under warranty, if still within the Corrosion Warranty. And don't let the Dealer tell you the panel has to be rusted through. The trunk lid is aluminum, and does not need to be rusted through for warranty coverage.
See here:
https://www.lincoln.com/support/how...ge/what-is-the-lincoln-warranty-on-corrosion/
Wish there was more we could have done to help you get a better resolution.
Good luck with whatever you decide to do.