I too am having an issue with the wrong additive (VC-8) being erroniously prescribed, as documented on another thread here. According to Ford, it IS important to get the right test media and the matching coolant additive (VC-12) for this new engine. I have had the wrong additive and the wrong test kit for about 15,000 miles. I was shown where to dip the test strips by the dealer (overflow), and they did not say the two systems did not mix.

I am in the middle of moving right now, but as soon as I can I will flush my contaminated coolant myself. The dealer has pretty much asked me to PROVE he sold me the wrong stuff. I have not had time to find my receipt, so it is likely this unnecessary expense will be on me.
Yet all I did was follow my dealer's advice. Bad advice. And apparently they aren't liable for steering me wrong.