Hi Hollis and welcome to our forum!
I doubt the manifest could help here because. My guess is that InfoPath does not parse references to the form's fields (xpath lookups on the DOM) when it parses the printSettings element.
We tried to add field values to footers and headers over a year ago for one of our customers. It was impossible. We checked with the InfoPath team at Microsoft at that time and they said it could not be done without going the route of a Word Print XSL. Word Print XSL is hard too for various reasons (XSL mapping to Word). I don't remember if we ever got that working. Greg would know.
Anyway, this was major feedback we took to Microsoft for next version. I am still hopeful that it will appear. :)
Patrick Halstead [InfoPath MVP]
InfoPathDev
Patrick Halstead
Project Manager at Qdabra