doPDF creates the PDF how it receives it, so changing those colors has to be made directly in Publisher. I don't have much experience with Publisher, but I know you can set the output to be different composite colors by going to File->Print->Advanced Print Settings. Here's what I've found in the MS Publisher help regarding the type of output, and you'll have to ask your printer guy which option he wants you to use:
Click Advanced Print Settings, and then click the Separations tab.
In the Output list, do one of the following:
Click Composite Grayscale to print a composite to a black and white printer.
Click Composite CMYK to print a composite to a CMYK color printer or proofing device.
Click Composite RGB to print a composite to a color printer.
P.S. You should edit your forum username so that it's not your email address, because this way you make your email public. You can change the username on the Profile page.