How do you create letterhead that prevents people from deleting logo but allows track changes?

Judging by screen shots: You appear to be using Windows version. You happened stumble into the Mac Groups

I will Move or attempt to move to correct forum.

If you can assume that all users will allow macros to run, you can prevent access to headers and footers by including the code from the article http://www.word.mvps.org/FAQs/Customization/ProtectWord2000PlusHeader.htm. That code is still valid in Word 2010 and 2013.

You may have to digitally sign your macro project with a commercial security certificate to overcome Word's refusal to run macros from folders that aren't on the user's Trusted Locations list.

If this works for you, you no longer need the content controls or the "cannot be altered"/"cannot be deleted" settings. Just insert the pictures and text in the header and footer, and set the pictures behind text.

I concur with Graham's recommendation.

As an additional comment, if the items you described are all in -- or anchored in -- the header and footer, they are safe from accidental deletion. There should be no reason for users to open or edit the header and footer, and nothing there can be selected or edited without deliberately opening them. That makes training for this issue easy: "Don't open the header or footer."

Unfortunately, if you extend the document to a second page, the user has to be able to edit the header on pages 2 through n. 

This is what the Different First Page check box in the Header & Footer Tools tab is for. The first page gets a different header than the remaining pages.

To set up the document initially (when there is only one page and the Different First Page box is not checked), create the default header you want to appear on page 2 and beyond. Then check the box; the header will disappear, but it will be saved in the document and will appear when page 2 exists. On page 1, create your logo and text in the header and footer.

As long as users edit the header only on page 2 or later, they won't change the page 1 header (unless they're incompetent or malicious).

See http://WordFAQs.mvps.org/HeaderFooter.htm for more.

We only want to prevent people from accessing the first page header and footer.  If we could apply a macro that would allow page 2 through n to be edited while keeping the first page protected, we might consider using it. 

If you set up a Different First Page header as described in my previous reply, you can use the macro from http://www.word.mvps.org/FAQs/Customization/ProtectWord2000PlusHeader.htm with the following alteration to protect just the first page header and footer:

Replace the lines

    Case wdEvenPagesFooterStory, wdEvenPagesHeaderStory, _
               wdFirstPageFooterStory, wdFirstPageHeaderStory, _
               wdPrimaryFooterStory, wdPrimaryHeaderStory

with this:

    Case wdFirstPageFooterStory, wdFirstPageHeaderStory