Bob, I'm not entirely convinced a nulled hair space is going to be enough. Acrobat is smart enough to correctly handle some pretty outlandish spacing problems in a PDF. That is, assuming those codes even make it into the generated PDF!
I'm afraid this will take some more drastic measures, such as converting the '@' character to outlines. (I'd try but I told my Acrobat to not automatically "fix" links long ago.)
Try it. I’m pretty sure it will work.
The point is you can’t turn it off for someone else and the default is on.
When it opens, Acrobat or Reader is scanning the document and adding links to the email addresses (or text URLs) automatically.
The only way to stop this is at the user level, in their own copy of Acrobat or Reader:
Go to Preferences >> General, and un-tick the box, "Create links from URLs".
Any text with an embedded link will still work, but automatically generated links from plain text will be removed.